How often have do you lose your balance on the rollers during one use?

None, once I learned to use them

How many times have you been injured using the rollers?

None

Would you be interested in a stabilization device that would help support the bike, but could be adjusted to allow some movement?

No. I actually have rollers and a trainer. If I want to read or watch tv while I’m stationary, I use the trainer. If I want to concentrate on what I’m doining, I use the rollers. I don’t really see the need for a mode of operation between the two.

How much would you be willing to spend on such a device?

$0

Where would be the best location on the bike to clamp for stabilization?.

I have actually seen people who use a fork clamp with their rollers—I don’t know if this is a custom job or if this is a standard piece of gear. With the fork clamped in the back of the bike can move a little, but the bike is esentially locked in upright. This is really just like using a trainer, though.