I wasn't aware that hose length could be an issue, although I had wondered. Right now I have the solenoid for my Greddy Profec B Spec II mounted near the battery with wastegate and IC piping coming in and T-ing right before the solenoid. This is a pretty long run for the drivers side stuff.
It shouldn't be hurting me right now as I have it turned down to minimum for my break-in, but once I start boosting I want to do it right.