I have been playing fragments of the campaigns in Halo: Master Chief Collection to be sure there are no problems with the game. Halo is generally very well developed but problems occasionally emerge, Cortana cannot help so Hard Core games is available.
At present Windows 11 beta is installed but testing games galore show it to be problem free.
Halo 3, The Ark (6th map in) however was a tad choppy in places. The game would freeze for a moment (40-100 ms) before continuing. Not sure what is wrong as the seaon 7 game works fine. I suspect there was some issue with the rendering engine. 343 is aware of the problem.
As play continued with The Arc the, Halo 3 seemed to stabilize better. So the freezing seems to be in the early part of the Arc map.
I played Halo: MCC through mostly to make sure my achievements are all done. Some of them are difficult but playing on Legendary is the Only Way to Play
I am certain that 343 will the time to fix the problems with Halp 3 before it is distributed. This is why legions of testers are recruited.