Great toothbrush - replaceable NIMH betteries (you supply) is way better than non-replaceable NiCad
I had mine for over 3 years.  Works like a charm.  It has been in luggage lots of times too.  I don't recall ever dropping it in a sink full of water or with the faucet running or dropping it into a toilet or a full bathtub or running shower, so I cannot credibly deny the 1-star review complaints.  I bought a bunch as gifts for my friend and his family and two of four (the ones the kids used) died in the first few months.  The 5-stars is based on my personal experience.  Just don't expose the battery end (bottom half) to more than a short modest spraying of water and it should last a long time for you.  You can buy 3 of these for the price of the traditional model and works just as good.  Get your heads in 6-packs at Costco - much cheaper 6 for the Amazon/Wal-Mart price of 4.  Yes the heads are expensive but if you don't have braces or whatnot you probably can push a 6-month replacement cycle.
Rating: 5 stars