Innies are nice looking on the outside, but who the hell looks back where the plugs are going in and out of the pedal (no side-jackassage allowed, top-jacks only, JTW) and sees the power-outie and says "gee, that looks so big & ugly compared to the signal jacks with plugs"?
Mainly, I always am cramming inside the pedal-confines, and need as much internal clearance space as possible — if not for my mods/intended-future mods, but also so I don't muck up Caps or other components when my lack of binocular vision-cues sets the soldering-iron tip too close to something.
Depth perception, wish I had it.
Outies uber-alles.