didn't tried the 11.2 but i always found protools kinda hungry !!! are you suing it in post only ? or even production ....
For X 3 , i bought it , installed it and unistalled it then !!lol
For platnum , i'm still thinking , it's solid , by the way , zero issues with melodyne or waveshell
itried vst 3 , did some test , zero benefit except the bypass , so i cancel the migration , some feature are killaz and make the X1 / platnum transition really worth it (don't know if X3 to platnum is) but the mix recall is one of those great surprise !!
What kills me is that whe you install platnum , it forces X1 to do a full rescan = all my registry is messed up (i used to customise plugins like name , entry ect)
And the worst thing is that there's 2 inventory now so it double my work , i spent the day doing this today and have to do it again tomorw if i choose to insgall also on my second comp !!