I think George is more interested in what others are running on the WRX ... what size will fit without rubbing. I think I would look at 225's ... wider for more lateral clearancegrip.
Usually stock size to the next wider one will fit without rubbing .... since there is usually plenty of clearance. Could measure the clearance with the present tires to the strut/springs and inside of fenders, front anti-sway bar (when the wheel is turned) etc. and then compare the tire sizes ... e.g. how much wider, and diameter (use Tire Rack.com ) and calculate whether the 225 (or whatever) will rub. Sometimes you might get rubbing at the extreme ends but you are seldom there with the steering cranked all the way ... even in autox. Or you can hold back a bit ... hear the rub, turn the steering wheel back a little bit. Just what I have done in the past. But usually you want to stuff the widest tire you can get on there ... to a certain point.