i think the bike matters less than the person who rides it.
scratch that: the bike DOES matter less than the person who rides it; it only goes as fast as you pedal it.

that being said, if all bikes are roughly equivalent, why not ride the one that makes you the happiest, or most comfortable, or both? chances are if you're comfortable you're lilekly to ride faster and further, and enjoy yourself more while you do it.

it's arguable that fixies are the foldable pocket-cameras of the bike world: incredibly simple, some might even say limited, which makes something as ordinary as a commute into something extraordinary.