These days this is a hit or miss area, for sure. It is not as bad as you might think however. I have a 1 year old Sony 52x drive that works well in an A2000 though a 2091 card with Asimware. I have also used new plextors, Liteon, and NEC and older Sony external units, on the A2000, and A500 and A1200 machines.
To be honest, the only drive I can remember not working with Asimware, was an older Phillips.