amazingly quite and smooth. seems solid and well build. I'm taking it slow and easy rather than diving in full throttle which is what i usually do. I discovered the itch that some talk about and I figure its a result of not taking the time to build up to the higher levels. So my first week is total positive experience.
My one complaint if I can call it that is that the led blue light is really really bright and painfully annoying at night or early morning in low light situations. would be nice if there was a dimmer for that. for now i just have to cover it with something.