Thanks guys!

Lots of responses and quickly - yeh!
'Officially' the vFire driver is
only supposed to be supported till 10.4.11, but I guess there might be some overlap into
10.5 at least initially. The post mentioned by Jumpeyspyder is the first I've heard of it.
Not sure I will take the risk - after taking a nosey at everymac.com (very useful site,
thanks GlynGoll) a first generation (2006) Mac Pro seems the best bet. Perhaps not the
last word in speed but enough for me as I am mainly hardware based, and it will still be
(hopefully) a big jump up from my G4 dual 1.25.
Thanks again everyone - eBay here I
come. Mac