Originally Posted by slindell

For Q factor - Campy is the narrowest, DA then Sugino. About the same order for clearance at the axle. Going with a narrower crank gives more room for moving the cleat in on the shoe or longer pedal axles (speedplay or DA). If you are going for a newer frame the chainstays might be wider than the steel ones you were used to so watch out for heel rub there too.
Road cranks have become wider over the years so going with extended pedal axles on a track crank can give you more clearance and be closer to your road bike if you are used to that.