AROS goal has always been to get it running on as much hardware as possible. Currently it run best on x86. I believe the PPC version has not been touched in awhile. Though I could be wrong.
There are three currently maintained architectures:
x86 - The most complete.
x86-64 - Should be almost identical to the x86 version (maybe a tiny bit behind).
PPC - Only currently maintained for the SAM and the Effika (AFAIK), should be at the same level as the x86-64 version.
The average user probably couldn't tell any of the ports apart though.
Oh, and when I last tested the USB on an x86 machine, it worked fine.
