I'd like to point out that just because you are able to get on Live (and not get banned) with a multi-BIOS TSOP doesn't meant that Live doesn't check the entire TSOP. Think of it like this: You go on Live with a mod BIOS, they ban you. You go on Live with the retail BIOS, they let you play. Now ask yourself why they would want to ban you? If I was Live and I saw someone with a multi-BIOS useing my orginal BIOS to access my services, I wouldn't really care what their other BIOSs were. Espically since they can't use they pirated materal, cheats, etc on my orginal BIOS; and there is no way (as of yet) to switch BIOSs with out shutting down the system. So IMO the main reason for people getting banned from Live when they are useing a mod-BIOS is because Live doesn't want them to be able to use all that they can with the mod-BIOS, only what they can with the retail BIOS.