Wow... Very unexpected. Works SURPRISINGLY well.
Sound is muddy. But framerates are solid. No screen tearing and only very minimal slowdowns that I saw. (I beat it up with a couple old ECS demos!) Pretty impressive. Especially considering it's such an early version.
Also, it didn't like my legitimate A500 kickstart. It just gave a black screen on startup. A kick.rom from a site I can't link to here solved that problem, though. :-)