I'm using DR Tite Fit 0.09 - 0.42. No higher or the whammy stiffens up too much.
Darknessfury, yes, 10s have a difference. Besides the obvious increase in tension, both strings and trem tension, 10s will afford you lower action than 9s. You get a thicker sound, but less snap. Your picking might improve because of the higher resistance of thicker strings, or it might fare worst because your pick don't slide pass the strings as easily.