After playing for a bit longer and getting half way through level 2 on Metal Slug without losing a life it locked up on me
Seems like it freezes at random points but it's still an amazing feat to see NEO-GEO games running in the first place    

EDIT:
It just locked up in exactly the same place again, when the first tank comes into the screen on level 2 i throw a grenade and it locks up. Oh well i guess i'll try some other games.

This post has been edited by Triforce, Wed, April 30th, 2008 at 01:32