Thanks for the link I'll have a look at that I'm beginning to get an interest in these demographic figures. Yeah over here with the major brands which are the same as those listed above except for Gateway my Dad's PC is an Acer and it's a bomb we bought it maybe 2 months before vista and the intel dual-core processors and seriously there isn't enough power to run even just windows XP it takes it around 5-10 minutes to go from 100% processor to idle ready to do any work at all. We paid around $500-600AU for an Intel Celeron D 3.3 Ghz, 1.5Gb of ram, and an ATI Radeon 9500 added later for around $100 to take up the load on some basic games. That was well whenever vista was released 3 years ago? So from personal experience the only computers I would by prebuilt would be laptops and small computer store builds where they care about the person but that's just me. I also wouldn't currently buy a dual-core gen. processor. Personally i3, i5, and i7 only, sure they cost a bit more currently but at least they'll last at least one OS upgrade.
Fingers-Crossed
So yeah personally I wouldn't buy mass manufactured but that's because I don't have to. It's a bit of a dilemma.