I have two pairs of the FSA cranks. They both developed a problem with the spider having some amount of play relative to the aluminum arm. On a fixed-gear, this is NOT acceptable because it messes with braking and speed modulation. It took 5 or 6 months for FSA to come up with a fix, and I still have to send them back for replacement. Pretty crappy, though. Right now, the cranks are useless.