a) where you gonna place it in an A600 ? Only options with full addressrage are PCMCIA (o.k) or clipped ontop of the 68k (bad cos you will need an accel)
b) who is gonna write drivers for such a beast ?
c) what kind of stuff do you plan to do on that A600 that won't be better served with an IndivisionECS ?
Pretty much all SW that utilizes a full GFX-card, also cries out for an 040 better 060 and will probraly run even better on a Morphed PowerMac worth 20p.