First, to anyone who wants to play on ps2 instead of pc, I'll just say: get Magic Swap Disc. Works perfectly, is inexpensive, no modding, doesn't void any ps2 warrenty. I also heard about using the memor32 memory card to put on memento firmware, which allows you to play without swapping discs. Only thing is, you have to rip the game off the disc to a pc, patch it, then burn it to a dvd-r (which I can't find a problem with since it's your own game you bought anyhow).
Another thing to keep in mind for MBAA on PC is that from what I understand, Sega Naomi (the arcade machine MBAA runs on) emulation is coming along quite well, and I believe MBAC B2 is supposed to work. There's little point doing that (what with the PC version and all...) but I don't see why MBAA won't work. Should run better than using a ps2 emulator, at least.