GVP DSS8+ is good 8bit sampler, if you are looking for fun/hobby stuff. Better than most other 8bit ones, gives good results even with A500.
And looks nice too:)
For serious work with A1200 are Delfina1200 (has DSP for realtime effects and realtime mp3 decoding with stock A1200), Prelude1200 and Melody1200. All of them use A1200 clockport interface and have AHI support. If you have towerised A1200 you can even use DelfinaFlipper with clockport connector.
