Honestly dude, it doesn't matter a whole lot. If you want to be faster work on your pedal stroke and ride more.

That said ... if I had a Rush Hour and wanted to throw money at it to make it faster I'd save up for a new wheelset ... for everyday riding (no tricks, but maybe **** roads sometimes) I'd go for: Mavic Open Pro rims, DT Swiss Competiton spokes, Formula small flange hubs. There, you just took a pound of rotational weight off your bike. I never skidded a lot when I road fixed so I could get away with "light" tires (compared to "skidding" tires) so I'd maybe buy some Michelin Lithions ... they're a good compromise between nice ride quality, flat resistance and price.

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