I'm with the parent. I had a MDD G4 until recently. I broke down and got one of the new minis cause it finally supported dual monitors. Though I wish Apple had a $1600 box that I could expand down the line. With 1 PCIe, 1-2 PCI, and 2-4 drive bays. I would have gladly given Apple the extra $1000 for that box. Especially if I could have thrown in different processors. My PowerMac 7500 was great for the time, I had 601, 604, dual 604, and g3 processors in that box.
I feel there is a hole in the mac line that the pro-sumer wants. Yes, it may be a bit harder to support with generic hardware. Apple can be dicks and claim to only provide support for official hardware. As I said before that's the Mac I want to buy.