I've had both - the SVP II is a wonderful preamp, but it won't do dirt. The SVP PRO definitely WILL do filth.
Both have the ultra low/high and bass, mid(s) and treble controls with line and DI outs, and the switchable graphic equaliser channel, but the SVP PROs have always been a bit noisy on the preamp outputs, whereas the SVP II was lovely and quiet.