What year and for what kind of riding on what bike? Getting your geometry right is just as important as quality of travel - so a great fork for one bike will suck for another.
IMO the '03 firefly is a great fork with the TPC+ damping in it. The newer ones with SPV are a matter of personal preference. If you like slow speed compression/pedal platform its a great fork. If you like it plush on the chattery stuff, it's not so great. I've beat the living snot out of my firefly and it runs great. The travel adjust broke a couple years ago, but I don't really care for travel adjust unless its a non-preloading type like Rockshox U-Turn(but then you're rolling the reliability dice).
ooh sorry, its a 2004 firefly, on an Azonic steelhead with 24 inch wheels. prolly gonna use it for dirt jumping, urban/skateparks, and free ride, so i think having adjustable travel will help with all the different types of riding i plan to do. i think it has SPV, but i would rather have the air anyway, just seems more adjustable to me i guess.
Its a great fork all around, and I think you'll like it. SPV with its bottom-out control would probably be great for DJ and urban. Beware of the travel adjust. It basically locks the fork further down in travel, so the spring is compressed and you don't have any sensitivity in the lower travel mode. Also, the travel adjust is fragile, and if you run it locked down on anything bumpy or abusive, it'll probably break and no longer be able to lock down.
From what I can tell, the only trailbike fork with travel adjust that is reliable for anything other than fire-road climbs is the Pike.