colinr said:
It's got a flip flop. I'm having it as fixed from the start, can flip to single speed if I can't handle it but I'm not backing down unless I really really struggle.
only thing you might find tricky is stopping with whatever foot you leave on the pedal at the top of the pedal stroke ready for pushing off again.
two ways of dealing with this: 1), front brake on, push forward on the bars, the back wheel will come off the ground, then you can pull the cranks round till your foot is at the top (need clipless pedals for this, but would recommend having them anyway if you haven't already got them)
, 2) just push on the ground with your other foot until the bike moves enough to rotate the cranks such that your other foot is at the top and can power down (can't do this on a hill start though)
the other obvious disadvantage of fixed is going downhill, but it does get you used to spinning which is quite good for you.