Hello ,
I bought a boomerang pad for the CD32 and it works fine with the CD32 , but in my A600 some games as for example Street fighter II can't use the 2 buttons...
So i bought a sega megadrive pad with 6 buttons and all games are working well with it (the 2 buttons recognised are the B and C) so i think it is one of the best pad for the amiga.
This answer just to help people who are looking for a pad !!