OGL2 sucks with MGS, from my adventures anyway. as everyone knows, i'm a huge OGL2 proponent. i was pretty excited when i got MGS:Integral from Japan, and i popped it into ePSXe, PSXeven, etc, and i could not get it to work properly with OGL2!
i found that OGL was the best bet--the PC FPS calc special fix seals the deal.