I routinely use a Jaycar 5m active extender cable in my setup. Like Marc says it takes a few seconds to recognise each time, so I usually plug it in first then my (unpowered) hub. QHY9, EQMOD, SSAG and FCUSB all run happily. I have to re-register devices if I run without the extender though, so I leave it in "circuit" even if I'm working close to the mount.
Nice to be able to get me and the lappy inside when at home in summer or middle of winter though
