I previously had a Phillips Sonicare Elite - for which I paid £80+; I was very pleased with that version, although I thought the price was steep, and it has done an excellent job on my teeth, particularly with keeping the plaque down.
I am very pleased with this new one as, at under £30, it does everything the old one did except beep every thirty seconds to tell me to switch to cleaning another section of teeth (which annoyed me with the old one and which I ignored on principle - who wants to be bossed around by their toothbrush at 7.15 in the morning?).
So I recommend this one thoroughly as I can't really see what extra the other ones on the market offer that is worth the extra money (and this version tells you how to change the rechargeable battery when it runs out (my old one lasted 2 1/2 years) - which the old version didn't allow me to change).
Marcus