I initially bought Powertap pedals to have the swappability. I was used to using Shimano pedals only.
First, Powertap uses a proprietary cleat that is ever so slightly different than a Look cleat. So I had to buy a few pairs to put on the couple pairs of shoes I had. And they wear out pretty quickly, which is annoying. Can't find them in a store, only online.
Then after riding in the pedals, there was a little play in them like the cleat wasn't fully sitting on the pedal platform, so I'd get slight movement with every pedal stroke. My feet never came out and it didn't affect my riding, but I could feel it and it drove me nuts.
I also learned very quickly that swapping pedals between bikes kinda sucks. Yes, it's just undoing a couple 'bolts', but I'd always get chain grease on me and almost stab myself with the big chainring.
At one point, I had a bit of side-to-side play in the spindle, then eventually the pedal just stopped working all together after I had them about a year. I must give PT credit, they took them back for warranty and I'm pretty sure sent me a brand new set of pedals and cleats. So that was a good time to sell them
I ended up just buying Power2Max cranks for both bikes and they have worked flawlessly. That also gave me the ability to go back to Shimano pedals, which was a really nice side effect.
