I bought the M540's because I liked the color. I've subsequently seen diagrams showing that the pedals are essentially identical, so it's a good thing I didn't buy the more expensive ones for performance reasons! BTW, I really like mine for commuting even though I'm on a road bike. They are 2 sided so no looking before you clip and the clips are recessed so wen I get to work I can walk around with click-clacking.