@BigBenAussie
Integrating UAE into AROS is not a trivial task. I'm not saying it is impossible but it sure would not be easy. Just integrating a 680x0 engine is tricky enough as you have all kinds of endian issues. The 680x0 emulation would not readily be able to easily share system structures with the native x86 code as it can on MorphOS and OS4.
Don't underestimate the power of the legacy emulation in OS4/MOS and the benefit of the native OS. I have tried UAE on some serious x86 kit and have ran system friendly 680x0 apps in OS4/Petunia on a mere 800MHz G4 with 133MHz FSB. I am absolutely not joking when I tell you it was the AthlonXP 2800 limping away clutching its' arse. I'm sure that other users can confirm that MorphOS' 68K JIT is similarly more than capable of giving UAE a good thrashing.
Even my lowly 603e 240 MHz can run 680x0 code on OS4 faster than an 060/66MHz (the old H&P 680x0 voxelspace demo for instance).
