Got it back last week from USA Optics ! working great so far without any issues like the mk2 35 had . USA Optics in Texas was dealer I went through . Wont be using them again , told one price at gun show and charged another when I picked it up , did not send it in till over 2 weeks after they received it and did not call after having it for one week to tell me they had it back from upgrades . had to to do all the calling and checking myself to get any answers on repair status . should have sent it in myself and not even messed with USA Optics.