I had the same concern on my Roo.
I had to reduce the aileron travel somewhat, the ailerons were way too sensitive with the throws suggested.
I use about 30% expo and you'll find you very seldom use full deflection anyway, so I've never had a problem with it.
Try reducing the travel on the ailerons to about 60% of what the manual recommends.
My manual recommends 3/4 inch up and down on the ailerons.
It will roll very fast at that setting. It's flyable, but I don/t like it that sensitive.
The elevator settings are about right 1.25" up and 3/4" down in my manual. The composite Roo s/b the same I would guess.

Pete Stapleton
Simjet Rep