To the OP, keep in mind that all of the pedals mentioned are MTB pedals. There are also road pedals, too. Without starting the road vs MTB pedal debate, I ride road pedals.

Those bike messengers and urban riders in general, who rode clipless liked MTB pedal systems because they could wear MTB shoes which are much more comfortable for walking. But if you intend to ride more than you walk, like commuting 10 miles to work then 10 miles home and that's it, I suggest getting road pedals.

MTB shoes have soles because dismounting to run or climb is part of MTB racing. MTB pedals are designed for quick mounting and shedding mud.

Road pedals emphasize float control, foot platform, and cleat placement. Fine tuning is important.



If you guys think that clipless pedals are awesome compared to toe clips, you will think that Speedplay Zero pedals are just that much more awesome than MTB pedals.

EDIT:

And I've ridden them all: TIME ATACs, Speedplay Frogs, SPD, SPD-R, SPD-SL, Eggbeater, Speedplay Zero, Speedplay Track Zero, LOOK, MKS...