I converted a U09 or something to a fixed w/ 700 cm wheels. No problems at all, and I run a front break. I more or less re-did most of the drive train (cranks, chain ring, fixed cog, new chain) and kept the french BB. all I had to do was change out the spindle. No problems really, and I have an almost perfectly straight and taunt chain line.

So don't hesitate! Go for it!