How to choose
First, Oral-B offers three lines of power toothbrushes: CrossAction, Sonic, and ProfessionalCare.  The Oral-B ProfessionalCare series is the top-of-the-line offering, and arguably the best in the industry.  My first Oral-B ProfessionalCare toothbrush finally started to wear out after ten years, so I certainly got my money's worth - especially if you count my dentist crediting my improved tooth and gum condition to my improved brushing.  All toothbrushes, chargers, and brush heads within the ProfessionalCare line are interchangeable.  They all perform the same cleaning action on your teeth, yet there is a wide disparity in price range between models.  This review helps guide the choice within Oral-B's ProfessionalCare line.<br /><br />===========<br />= OVERVIEW =<br />===========<br />Amazon currently offers the 7400, 7850, 8850 DLX, 8900 "OxyJet", 9400 "Triumph", 9900 "Triumph Smart Guide", and 9950 "Triumph Special Edition".  You can find most of these on Oral-B's web site, but it is hard to use and difficult to compare.  Here's the summary:<br /><br />- 7400 is a short-base fully functional basic model.<br /><br />- 7850 and 8850 DLX are tall-base models storing extra brush heads under the lid.  The 8850 DLX includes extra brush heads in the package.<br /><br />- 8900 "OxyJet" is a 7850 plus a second appliance (NOT another toothbrush): "an oral irrigator with innovative micro-bubble technology".<br /><br />- All Triumph models have Oral-B's newer "attractive design" for both brush handle and base, but still use the same brush heads and cleaning action as all other ProfessionalCare models.<br /><br />=======<br />= BASE =<br />=======<br />The 7400 has a short squat base that charges the toothbrush like any other base.  For a single user, this cheaper model is the one to get as you will just keep your brush head on the toothbrush.<br /><br />The 7850 and 8850 have a taller base that includes storage for up to four brush heads under a lid that provides protection from dust - and from sink area sprays.<br /><br />The 8900 OxyJet has a dual base for charging the irrigator at the same time.<br /><br />All Triumph models have a mid-height base with storage under a clear plastic lid.  The 9950 Special Edition also includes a travel charging base.  Personally, I pack a manual toothbrush for trips and leave the Oral-B at home for a few days.<br /><br />=========<br />= HANDLE =<br />=========<br />All the handles are the same to me.  Admittedly, some will find the Triumph handles slightly more attractive.  Also, I suspect there is an increase in battery capacity as you move up from the 7000 series through 8000 and up to the 9000's, but I have not been able to verify through documentation.  The 8000 models I used personally have plenty of charge for two people to brush in the morning - and probably more, though I never tested.<br /><br />The 9950 Special Edition of the Triumph model includes a second handle so that two people can brush at the same time.<br /><br />==========<br />= BRUSHES =<br />==========<br />As noted in the introduction above, all brush heads are interchangeable.  Buying a more expensive model does not affect the cleaning action on your teeth.  The 8850 DLX bundles one of each type of brush head into the package.  See my uploaded photos for details.<br /><br />=========<br />= TIMERS =<br />=========<br />This almost inconsequential feature was a major differentiator that set Oral-B power toothbrushes apart from their competitors in early reviews by dental professionals.  All ProfessionalCare models have some degree of timer built-in so you'll know that you've brushed your teeth long enough.  The basic timer interrupts the brush spinning action three times in rapid succession after two minutes of brushing, so you hear a brief "stuttering" as your signal.  All of today's models do this, along with a single spin interruption every 30 seconds so you can perceive progress.<br /><br />The Triumph models add an actual LCD display into the brush handle so you can see exactly how many seconds you've been brushing.  But who can look at the handle while brushing?  The higher-end Triumph Models, specifically the 9900 and 9950, include a separate "Smart Guide" displaying your brushing time on the sink counter.  It seems like expensive overkill to me personally, but at least you don't have to stop brushing to see how long it's been.  The same is true for the spin stuttering models, so it's really a matter of choice.<br /><br />========================<br />= GENERAL RECOMMENDATION =<br />========================<br />From years of experience I can recommend the Oral-B ProfessionalCare line with confidence.  Ultimately the choice between models comes down to individual preferences.  Generally speaking, the cheapest model (7400) is a good fit for single users because there is no need to store extra brush heads in the charger base.  A tall base with storage is a good fit for couples, such as the 7850 or 8850 DLX.  The high-end Triumph series is for those willing to pay more for gadgetry and aesthetics.
Rating: 5 stars