I used to play Sonic DX Director's Cut for Gamecube and I had some chao there. I remember I had some pretty good chao, I had some speciality chao that were trained in just one area, like flying or swimming or hero or villian. I also had my favourite chao that was really high in all areas. I had some problems early on whereby my chao save slot would keep getting deleted somehow and I'd have to start again I hope that doesn't happen again
I'm sure its nothing with the game though! Its probily the memory card or the gamecube. I prefer Sonic Adventure 2:BATTLE i think they did chao a bit better in that game. But Sonic Adventure DX is pretty good becuse of the Garden size! (There huge!)
I have Sonic Adventure 2 Battle. My best chao is on that game. His name is Echo and everything of his is 99 level and he's won all the prizes in the races and won all the chao fights.
I also have Sonic Advance. I have a chao named 'Moonray' on that game. He's pretty good for a GBA Chao.
Sonic Adventure DX is my worst game for chao. They're all bad and I keep getting my buttons mixed up when it comes to them. That's why i don't go near the chao all the time.