You are so right....
I got Win7 64 for £30 on the student deal a while ago and put it on my games machine (since XP needed a reinstall anyway. Works very well, is shiny, pretty much as good as my Mac Mini. Adequate for that price.
A while ago (2 years?) I got Vista Ultimate 64 on the same deal, put it on my 'messing about' PC (retired games machine). Works OK, not quite as shiny, spat it's dummy out regarding graphics cards, some wierd stuttery behaviour now and again, but not too bad. Again, adequate for the price.
In both cases the experience of actually getting the OS installed and working was on a par with breaking a bone or coming down with a serious (but not life-threatening) gastro-intestinal disease. Maybe I'm just unlucky but given that every single problem I ran into was resolved by googling up other people's fixes for the same problem, I'm certainly not alone. All that rubbish and paying full retail too? I don't think so.
Fun fun fun: If Win7 repeatedly hangs on 'completing installation' and the problem can't be fixed by feeding it the correct WHQL SATA drivers, you can work round it by installing to an IDE drive, using a LiveCD to clone that working install onto your SATA drive, rebuild the MBR, disk IDs etc. Then you boot up off the SATA drive and everything works flawlessly.
I'm a PC and I have a high pain threshold.