I've only been playing stuff that doesn't tax the Amiga on a N3DS, so I didn't pick up on the performance hit.
I have been savestate scumming my way through a bunch of games, and I noticed that after about 10 or so save/reloads, it freezes on the state load screen. You can hit the home button...
I just signed up for this site just so I could tell you how much I absolutely love this emulator. it is so unbelievably awesome to have a clamshell form factor portable Amiga.
Button mappings are great! I wish there was a way to adjust the mouse sensitivity, is there a way to do that?