IMO, FP-10 is better than CLP, either the GI surplus stuff or the commericially-sold Break Free CLP. In my experience it's a better lubricant, MUCH better cleaner, and from test results I've read online, is a better rust preventer.
Note that while FP-10 is better than CLP IMO, CLP is still a good lube and rust preventer. I've never thought much of it as a cleaner, though.