I've had four surgeries on my right knee, most recently bilateral release to try and reduce the dislocations to the right. It hasn't worked. Despite intense Physio my knee is still subluxing and dislocating although the pull to the right has reduced slightly but unfortunately my knee cap is just slipping forwards. I've also had surgeries to my shoulders to tighten the muscles within 3 years bot shoulders have loosened and stretched out.
I guess it depends how bad and frequent your dislocations are and will,even a slight I prove net with surgery improve your quality of life? I'm not sure if I will go through surgery again as each time it is a bigger risk and the outcome is the same- my ligaments/muscles etc etc are too stretchy and will over time stretch out and undo any good surgery has done. Also surgery that might fix others can make peeps with HMS worse. Two surgeons have recommended different surgeries for me but both have pointed out it could make me much worse and lose more than I could gain mobility wise. It's a tough tough choice. A route I will only go down if my mobility becomes so bad that it can't be made worse than it is.
Saying that, we are all different! And what works or doesn't work for one may do so for another. Good,luck with whatever you decide to do.