I'm quite sure I saw OS4FE_RC1 on WinUAE running in better than AGA GFX.

I'm also quite sure noone wrote a PPC native version of UAEGFX.

I'm actually 100% sure that people running it on actual Amiga-HW but lacking PCI have to resort to 68k drivers for the likes of Cybervision64, Picasso2/4 etc.