My fixed is super light (less crap on the bike), quiet (no chain slap, derailler rattling, etc. when curb hopping), and fun. I ride fixed to improve my stroke, cadence and endurance for mountain biking. There's so little on the bike that it has a minimalist elegance that the designer in me appreciates. Since the chain is so straight and attached so directly, it's more efficient than a geared bike in the exact same ratios, so it's fast.