I've tried doing what the guy says in that video. I saw it a while back but his method only works on the very, very rare occasion. I tried about 50 times, which took ages, and got it to work once. It crashed at the very next loading screen though, so it's unplayable.
To get MGS working, you need to enable SPUsync in fpse.ini, but to my knowledge, that option is only available in 0.10. Also, that doesn't really fix the issues very well. It still has a tendency to crash at every opportunity, mostly when the screen goes black.

*EDIT* I would definitely recommend getting a PSP (not the PSP Go though) and putting a custom firmware on it. With that, almost all PSX games work flawlessly, and those that don't generally have fixes. There's also a great deal of awesome homebrew available for PSP. Oh, and Syphon Filter Dark Mirror / Logan's Shadow are brilliant!