Originally Posted by Scottybigs

I ride the A530's on my touring bike for the reason you described--wanting the option to ride the bike casually around town with whatever shoe, but then clipping in for longer rides. They're a great, versatile pedal in that regard.

For riding fixed, though, I do enjoy having a double sided pedal and not having to think about it. I rode with Shimano A520's for a while, but would get annoyed in traffic when clipping out and trying to clip back in again. It's not the biggest deal, really, but since I already had a pair of M520's I switched back and haven't regretted it. Something about cranks spinning and clipping in with ease just makes it worth it.

My advice: grab a pair of A530's and find out for yourself. You can always switch back to your M520's if you want. Wellgo also makes a fairly popular platform/SPD pedal, too (big fan of the oil port for maintenance): Wellgo R120B Sealed Bearing Road Pedals | Chain Reaction Cycles