Hi, JDP. I'm at almost 6 months out and think that my flexion is between 95-100 most days. I was able to get it past 100 during PT, but I have discontinued that and haven't been measured in about a month. I'm choosing to put my faith in being patient and allowing my knee to become fully healed. I think I still have interior swelling, but that's very hard to prove--just feel quite a bit of tightness, and some discomfort on stairs, still.
I was worrying about flexion, as I kept seeing my surgery twins passing me in that department. Recently I realized, though, that I can do just about anything I want to with the flexion I have right now. Stairs are still uncomfortable, and going down with good form is quite the challenge. Other than that, daily activities go fine, and i can walk at least 2 miles without discomfort. Shopping, standing in lines, and extended periods of sitting in restaurants have all mostly resolved themselves. So I've decided not to worry any more. I would like to be able to ride a real bike on a real street someday, safely and comfortably. When I get there, I will feel I've "arrived." (I can pedal our exercise bike okay now.)
I had an MUA at five weeks when my flexion was around 75 degrees. Although it seemed to help me get to where I am now, it was not a "magic bullet" for me, and I wouldn't say "Go for it" unless you are completely convinced by your OS's rationales. The procedure sent my healing back several weeks and caused additional swelling with which I had to deal.