MGS is one of my favorite games, and as such I've been using to test many of the new plugins that come along.
here are the most optimal settings I could attain after much expirementation.
FPSE 0.9 or ePSXe 1.0.1 you will probably find MGS to be most playable on these two emus. Currently, I am still testing ePSXe 1.4.0 to see what combinations of plugin's I can use to get around a consistant crash during the video sequences in the NTSC version (I don't have the PAL version so I can't confirm if it has the same problem)
anyways here are my MGS settings
pete's GPU 1.50
Fullscreen On 800x600 32Bit color depth
R8 G8 B8 A8 Texture quality
FPS Limit ON
Frame Skip: (OFF ePSXe) or (ON FPSE optional if you use interpeter mode)
FPS Auto Detect ON
Off Screen Drawing: 3-Enhansed
Famebuffer Textures: 2-Gfx card buffer
Alpha,mask,advanced blending options ON
Special Game Fixes: ON
(inside special game fixes)
PC FPS Calculation (ON for ePXSe) (OFF for FPSE)
Framebuffer Read: ON
Prodigy SPU 0.1
Buffer Length 40
(Note: as long as the inteval reads 10 you should be fine)
CDrom Internal (ePSXe), ISO, or Pete's (for FPSE users who use win9x, win2k users should use the native FPSE CDRom plugin)
If you have a fast computer, I recommend using FPSE and setting it to interpeter mode. Because, this will produce the most accurate emulation of MGS on a free playstation emulator.
now only if I could get the those movies to play faster in FPSE...oh well back to work again.
departing words...to my dissapointment the current version of Prodigy doesn't support saves states. But it is the best sound plugin to date for MGS.
Hope this helps for anyone who's a big fan of this game.