Fox Float CTD Evolution vs Fox Float CTD Performance What is the difference between Fox Float CTD Evolution and Fox Float CTD Performance? Except that one is most expensive and better? I mean real difference...
What's actually increasing the cost in performance fork is it's construction qualitiy. It's slightly better in terms of durability and a bit lighter. Depending on the year of make, performance may also include a new technology or system that the evolution (which is the basic lineup) won't have (thus making it more expensive). Think fox's lineup as this:

evolution -> sunday family ride

performance -> more intense riding

factory -> pro riding