Philips Sonicare Flexcare Plus Sonic Electric Rechargeable Toothbrush, HX6921/30

A great electric toothbrush, the sonicare is amazing. I originally purchased this model over the others because of the more narrow handle on it, but I much prefer it over the lower-end model my girlfriend has. It has a clean, professional, and adult look to it and fits the hand like a solid toothbrush should instead of like a Dremel tool with a toothbrush attachment like the lower-end models do.Features--------------------It wasn't very clear from the product description when I first ordered it, but one of the buttons on this device is a mechanical button (the power button) and the other is a capacitive touch button (the mode button). The capacitive touch button is extremely well designed, requiring a very deliberate touch while the brush is off in order to change the mode. There are a handful of modes the brush can run in, with a couple giving a pulse pattern instead of a constant run. Largely the difference is the amount of time the brush will run, but if the "quadra-pacer" setting is used, the mode being used changes when the pacing is signaled.In addition to these modes, there are two settings that apply to every mode that aren't selected the same way. The first is a "quadra-pacer", and the second is a beginner mode. The "quadra-pacer" is a feature that when turned on will cause the brush to pause briefly in it's normal routine to notify you that 1/4 of the cycle is done when, and how frequently this actually occurs depends on the mode selected however. The beginner mode is intended for those unused to electric tooth brushes and supposedly starts with a weaker sonic brushing, ramping up over time as the brush is used again and again. Beginner mode can be reset to start over again, or it can be turned off completely (like I did), but is enabled by default when the brush is received.Of the modes, the most basic is the standard brushing one. It runs for 2 minutes before automatically shutting off, and if the quadrapacer is enabled it will pause very briefly every 30 seconds. Another mode is a gum massage mode that slightly changes the pulse frequency the brush runs at, and sets the time for 1 minute. In this mode the quadrapacer notifies you every 15 seconds. The mode I use for my regular brushing is one that combines both of these. The brush runs each of the two modes back-to-back without pause, for a total of 3 minutes of running time, and if the quadrapacer is on it will actually provide 8 notifications, the first 4 in 30 second intervals, then the last 4 in 15 second intervals. Additionally because its running the different modes back-to-back, the pulse frequency of the brush changes slightly for the last 1 minute. This isn't really a significant change though and is barely detectable even when waiting for it. There are also a couple other modes, including a refresh mode that runs for 1 minute with the normal brushing pulse frequency.Battery-----------------------------The battery is a sealed internal rechargeable battery that recharges wirelessly from an included base unit. The actual base unit is only a little bigger than the base of the brush, and about 1/2" thick. It has a small stud that fits loosely with the bottom of the brush to orient it. Included is also a larger plastic case that the charging unit fits into that provides a larger and more stable base, small mounting studs for 2 extra brush heads, and hooks/space for wrapping the cord to keep it out of the way. The really major selling point of this though, isn't how easy it is to charge (which is incredibly simple and fast), but the fact that it almost never needs to be charged. The usage time listed is 2 weeks between charges, but using it in the longest (3 minute) mode usually once a day, but occasionally twice a day, I easily make it closer to 3 weeks between charges. This makes it an absolutely perfect travel companion since you just need to make sure it's charged before you pack it and then don't have to worry about bringing the charger. At the bottom of the brush is a set of 3 battery lights that clearly indicate the battery level whenever the brush is used and for a few minutes after. Putting it on the charging base will cause all the battery lights to fade on and off while it's charging until they all stay solid on when it's fully charged. When the charge is low, it will pulse only the lowest battery light whenever it would show the battery level, and when it's critically low the light color changes to orange instead of yellowish-green and the brush will occasionally pulse strangely while being used (clearly an indication to the user to check the battery level and charge it). Charging it seems to only take 30 minutes to an hour from a nearly empty charge, but your mileage may vary.Usage & Additional Parts-----------------------------------Knowing this was clearly going to be used in a wet environment, the entire brush is sealed and waterproof. I use mine in the shower, so I keep it laying sideways on a shower rack when I'm not using or charging it, pick it up to use it while I'm showering, rinse it in the shower when I'm done, then put it back on the rack (laying on its side). The only gap in the entire unit is where the replaceable brush head attaches, there being a small gap between the bottom of the brush head and the top of the motor unit when it's fully seated. This isn't particularly noticeable since it's right below the colored band on the brush heads, but it does mean that the top of the unit needs to be slightly cleaned of build up whenever the brush head is replaced (just to keep it clean, not because functionality is in any way affected). In the package for this brush, you receive one brush head, the hand unit, a charging base that plugs into the wall, a plastic cover for the charging base (described above), and a travel case that fits the hand unit (without an attached brush head) and up to two brush heads. The travel case has been unbelievably nice in my experience, making it very easy to take the whole thing with me in my luggage without having to worry about getting dirt on my brush heads or somehow destroying the short metal drive shaft that extends from the hand unit into the brush heads when they're attached. The ability to carry two brush heads seems like overkill to me, but the case clearly isn't extended or the design modified so two could be handled instead of just one so it's hard for me to fault the design. Brush heads are rather standard, you don't need to buy OEM despite what some reviewers have said, you just need to find brush heads that specifically fit this model of unit, and they generally last 2-3 months before they need replacing.

Sonicare Flexcare PlusI was skeptical at first, and I had been using Oral-B's brush system since around 1996, but always knew about Sonicare. I didn't realize how Sonicare really "vibrates" the tooth brush 31,000 times a minute because I can certainly tell after using it. There are no mechanical moving parts with these brushes, the brush head just "vibrates" rapidly causing the toothpaste/fluid mixture to agitate and flow through gum lines and in-between teeth, while the brush works gently and rapidly to remove stains/debris from the teeth. I watched YouTube videos demonstrating how to use the Diamond Clean Sonicare system, bottom line is that I am truly impressed with the performance of Sonicare after using it for the first time.Oral-B wasn’t bad, but it doesn’t feel “as clean” after using those brushes. The Oral-B system is similar to a random orbital buffer, where the brush head rotates back/forth rapidly. There are numerous Oral-B brushes but I always found myself using the Oral-B Sensitive and Precision clean, and never liked the Floss Action or Tri-Action heads. The brushes cleaned my teeth but it always felt like it was rather rough on my gums and teeth without being able to get into the deeper nooks/crannies. The Sonicare system seems (at least in my opinion) to agitate the fluid enough to allow it to clean other areas that a brush normally cannot reach.I purchased compact Diamond Clean heads after extensively researching Sonicare's confusing line of brush heads, before I actually bought a Sonicare toothbrush. I noticed the Diamond Clean was the most expensive but highly rated tooth brush available, with 7x the cleaning power. I was curious to see what differences (if any) there were with the actual Diamond Clean tooth brush versus a less expensive model such as the Essence or Flexcare series. I quickly found that most of these brush heads are compatible with the Flexcare and Diamond Clean, with the Essence being a low-budget line. There didn't seem to be a difference in performance between the Flexcare Plus or the Diamond Clean, so I ordered and received the Flexcare, and used the compact Diamond Head brush for my teeth. The Diamond Clean seemed to just have a fancy USB-charger for the travel case and a fancy rinsing glass/charger base, and would come with full-sized Diamond Clean heads. There’s nothing wrong, but it was substantially more expensive than the Flexcare Plus.The Flexcare Plus comes with a single full-sized ProResults brush, which I felt was too big and I didn't like the feel. The compact Diamond Clean has a much higher bristle density, with lots of tiny bristles packed into an area for maximum cleaning. The smaller size allowed me to focus on tight spots as well as cover the larger surface areas (flat parts of teeth, biting surfaces, etc...)The Flexcare Plus comes with a charger base that also includes a travel charger with a base that you can wrap the power cord around. The Flexcare Plus utilizes a Lithium Ion (Li-Ion) battery pack, that should be good for at least 2-5 years. I would have preferred a Nickel Metal Hydride (NiMH) battery because they have a longer lifespan.The Flexcare Plus is quieter than the Oral-B Triumph and Precision Care series brushes. It’s basically the same difference between using an electric hair trimmer with and without the attachment installed: a high frequency mosquito “buzz” (Sonicare) versus mechanical parts moving back/forth rapidly (Oral-B). If I accidentally touch my tongue or lip on the Sonicare brush head, it sort of feels tingly due to the vibration from the brush head.Overall: 5/5 stars, I am very impressed with Sonicare! There are no moving parts on the brush head, it relies on high frequency “vibration” of the head which results in a brushing action as well as agitates the toothpaste/fluid to clean your gums and teeth. Since I’ve already been using Oral-B for over 15 years, I am not new to electric toothbrushes and didn’t have any problems adjusting to Sonicare immediately. I will keep comparing the Sonicare with my Oral-B Triumph in the near term, but would highly recommend you try a compact Sonicare brush head for more control and precision, similar to the smaller Oral-B heads.