Has anyone tried this? I got sent one to try (Bzz campaign) and it is seriously amazing. Bzz have sent me so much stuff that's been a complete waste of time-this is the first thing I've been properly impressed by. I have such hard, cracked, revolting feet and this thing just whizzed them smooth in 5 minutes flat! So satisfying. Bloody loud though. God knows what the neighbours must be thinking 
If anyone is fed up with foot files and/or horrible feet, I can really recommend this little gadget. First beauty gadget I've had that's actually worth it I reckon. (Though I've never tried a Clarisonic!)