Seem to have had a bad rep in the past but all sorted for 2009? How do they rate against equivalent RS/Fox?
there was a thread on these last night - specifically the 55 ATA. I've cut and pasted what I wrote there... I haven't had much time on Lyriks, 36s or Wotans so can't really compare, but I do know what good suspension should feel like (lots of experience with Marzocchi coil-oil forks and their high-end damping cartridges) and I think the 55s are great.
I have the '09 55 ATA Micro. it's a good fork - fairly light, tracks beautifully, very stiff in the right places, inspires a lot of confidence. All the adjustments work perfectly (TST Micro compression, ATA travel, rebound). I think I actually preferred the old TST5 to the TST Micro (not really much need for the fine adjustment I reckon; I generally want my fork either as plush as possible or locked out since I have a strong aversion to riding uphill offroad... but I'm sure some people will find it useful).
as far as the action is concerned, for an air fork I think it's pretty plush. The wiper seals have quite a bit of stiction to start with, but this fades once you've bedded it in (takes a while!) The hardest thing is actually setting it up, since the manual is useless. Take your shock pump out on the trails with you and be prepared for it to take several weeks before you're happy with the settings. The quoted air pressures for main chamber and PAR assume that you carry a washing-machine on your back when you ride - you'll be using far lower pressures. I found that the standard rule of "30psi more in the PAR than the main chamber" didn't work for me - when I tried this, the fork had far too much sag but then ramped up so quickly that I could never get full travel. But if you're willing to put in the necessary effort for setting it up, you'll end up with the best air all-mountain/freeride fork on the market.
Would I buy one again? Actually, no - I'd wait till September and get a 2010 55 RC3 Ti, simply because I prefer the feel of coil forks to air springs. But if you like air forks then I don't think you'll find one better than the 55.