i've been considering an air shock for my UFO ST. i don't know many people running air in the back, and i had a few questions: i'm not aware of many options out there other than Marz and Fox. is there anyone else out there makeing a DH air shock? i've not heard much noise about the Fox DHX Air getting "stuck down" lately. is this a still a problem with the product? i've heard the Roco Air shocks have had issues holding pressure (i have a bud with one and he is having some troubles). is this common (or is my bud just a hack )?