Great If You Want A Slime Factory - But There's a Cure
Despite rinsing and wiping the exterior of this unit after each use, a pool of slime soon forms in the charging base.  It's even worse inside the top of the handle, visible when the brushing element is unscrewed.  If you want to avoid a disgusting mess, you really need to disassemble this unit every day for a thorough cleaning.  That's a lot to ask for a tool that is supposed to make our lives easier.  I used a previous Sonicare model for years without ever encountering this issue.  My wife's toothbrush is identical to mine, and it has exactly the same problem, so there's pretty obviously a serious design flaw with this model.<br /><br />A CHEAP FIX:  The problem is that the gaskets in the brush head don't seal out liquids.  One possible solution is a product called "Sonic Seal" [[ASIN:B001S2PLNK The Sonic Seal for E-Series Sonicare Replacement Heads (3 Pack of Blue, Pink, Frost)]] available on Amazon -- currently 3 for $16.95.  Pretty expensive for what's essentially a toothbrush condom, so I tried making my own in three easy steps. (1) Take a latex glove and cut off one of the fingers. (2) Cut off a very tiny section at the end of the detached fingertip (the resulting small hole will stretch temporarily in the next step). (3) Slip the glove finger down over the brush head, leaving the tip end above the top gasket of the brush head, and pulling the rest of the latex down to where the brush head joins the handle. Voila, no more slime build-up.  (Keep the glove on hand in case you have to make more protectors later on.)
Rating: 2 stars