Air-cooled, which was a crucial consideration. I know that even the early, typically leaky, liquid-cooled dual G5s can be pretty easily fixed in many or most cases, assuming the PS has not fried, but I did not want to go there. If I could find a dead one locally for small change, I would snap it up and get out the tools, but when buying at a distance and for real money, it is only sanity to be cautious.

I had indeed thought of a Quad, and would love to have one, but the price differential is significant between the Quads and what I paid (1:4 - 1:6, by your reckoning). Quads are not yet retro enough to be cost-effective purchases,given what you can buy a Mini for — or indeed a MacBook Pro. Meantime, I wait and wonder if enough of them will survive their cooling systems/ be looked after well enough for one to come my way.