Neither MorphOS nor OS4 currently fully support all the features of the Radeon92xx and below, OS4 doesn't even supporet everything a Voodoo can do (not sure about MorphOS). 3D and 2D drivers on Radeon92xx are way ahead in MorphOS compared to OS4. Hard to "keep up with AOS" under those terms.
The only problem for MorphOS & GFX I see are:
- cards can (will soon) only be bought used - no decent way to go beyond 1920x1200 as MorphOS does not support DualLink DVI and no supported card has HDMI