So I've got
Metal Sonic Overdrive, a great fan-made version of Sonic the Hedgehog by Darkon. It has new levels, music, and graphics. Even has several selectable characters including Kirby and friggin' Somari (Mario)!. $15 USD, several copies available.
These cartridges are brand new. All the components are brand new; cart shell, PCB, ROM chip, nothing is taken from sacced carts or anything. They're tested in a US/JP model 1, a 32X, a Nomad, and some clone systems. The only hiccup is the cart shell. It's a universal notched style shell but it'sa few mm thicker than a normal USA cartridge, about the size of a 32x cart. I don't have a model 2 to try, but in a USA model 1 it's an EXTREMELY tight death grip fit. However, if you use a Game Genie, Action Replay, Mega Key, or any other type of passthrough cartridge it's no problem at all. It also seems to fine in most clone systems since they have oversized cart slots. The game itself works in every system I've tried, it's just the cart shell that's a problem.
If you're interested just drop me a line.
-Thanks!