Fit - the only ones I have found so far that fit me right are small Giordannas
Look - Not flashy, no large logos of any kind (including team)
Price - Maybe this one should be first because I never look at them unless they're on sale.
Extras - Does it have a mid length to full length zipper, good pockets, reflective bit or bright but not flashy colours (ie white or yellow).
Shop - Don't buy from Team Cyclist, Sierra Trading post is usually pretty good though.