First I must say that I received my Sonicare free via BzzAgent. If I were to pay the $160 to get the brush myself, I would probably be hesitant. That's really expensive! But this brush gives such a clean feeling, that it really is worth the price. The company does provide a 90 day money back guarantee if you are not satisfied, so what do you have to lose by trying it?
This brush had a faint buzzing noise during use, but it's much quieter than ones I've used in the past. The motion of the brush doesn't leave me feeling like I've been beat up after brushing. With a click of the button I can brush my teeth and know that it's time to move on to the next quadrant when the brush pauses. I have absolutely smooth and clean teeth in two minutes. The modes available with this brush are clean, sensitive and massage. I am using less toothpaste than I did with a manual brush. I guess this is because of the movement of the brush, causing more foaming than I ever could with the work of my wrist.
I put my brush head into the sanitizer after every use. I can't honestly say that I KNOW it's really killing 99% of the bacteria it's claiming. But, my brush heads are looking the same way they did when I got the kit.
If my Sonicare were to stop working tomorrow I would probably try a less expensive model. Sonicare has really impressed me.