Clean Teeth, short battery life [SEP] I am enjoying this toothbrush. After a good brushing job, my teeth feel almost like i left the dentists. The 'sonic waves' really do dislodge plaque and leave a very clean mouth.<br /><br />Great for me because i travel frequently and do not feel like carrying a toothbrush charger.<br /><br />One odd thing, though, is that my first set of batteries only lasted a week. I just put in a second pair of batteries and am waiting to see how long they last. I brush twice a day, so ordinary amount of usage. I tried a pair of fully - charged NiMH batteries today (I think all NiMH rechargeables are 1.2 V) and the tooth brush would not start. Seems that it needs 1.5V batteries. It worked fine with ordinary alkaline batteries.