Bc2, I have the oxford heated grips. The large diameter works with my hands. They will get so hot that you have to turn them down, so power is not an issue.
The grips do all they can, but im not a real fan of the concept.. They work better on my c14 because i have hand guards to keep the wind off. On the ninja, the back of my hand will be freezing, while the inside is too hot to hold the grip. This is talking 35-40 degree temps. They are nice when its 50-60 to take the edge off. They are cheap and easy to connect, but overall, i think ill try the gloves.