I use Speedplay Zero after having used X Series for many years.

I switched about two years ago when after starting to use SPD on other bikes. Unrestricted float was leading to poor form when I was tired at the end of long rides and I found that I enjoyed the narrow range of float with both SPD and Zero.

As a practical matter it would be difficult to unclip Zero's inadvertently. You have to really give them a twist. It shouldn't be a concern.

I'm not sure about the Light Action pedals however, how easy it is to unclip. There are some who try to pass off Light Action as Zero's on the used market/Craigslist so be careful if you are looking at used.

Also, walkable cleats do come off. I've lost one.


-Tim-