Fuck the GBA version of Puzzle Fighter-- my game data erased itself more than 10 times playing through the different modes. I don't know if they ever fixed this problem or even acknowledged it (I know it wasn't just my cart because many people on messagedboards had the same problem), but at this point I couldn't care less. Such sloppy development/game-production. Oh, and I eagerly await the "What data is there to save in puzzle fighter anyway" obligatory defense posts.
Get Puyo-Pop or something made by people who know how to produce cartridges without self-terminating memories.