As someone who uses a ton of i386/x86 hardware for work (UNIX systems), I can tell you those "hand-built" systems come no where close to the quality of components used in a Mac. Apple builds tanks. In 15 years of using Macs, I have never had one hardware failure so I have ended up with a closet full of Macs. About 2-3 years of use of a x86, they are pretty ragged out. They just run so damn hot compared to a Mac.
Yes, you can build a PC cheaper. I just don't know if I want to rely on it working day in and day out.
I would never compare Windows 95 to Mac OS X. Windows XP is easy enough to beat. Why would you want to use an OS that limits you to 80% of your bandwidth and you have to report to Bill Gates and Microsoft if you want to change your system up not to mention that Bill Gates refuses to let you see one line of the operating system source code? Talk about proprietary!
Please get real. How many hand built machines have you built? Except for motherboards and cases, the same components are available to everyone. the same memory chips, the same video cards, the same SCSI cards, the same disk drives, the same DVD burners.
You want tank cases? Try Supermicro or LianLi, or even the server cases made for Dell or IBM.
As for motherboards and CPUs, I have seen exactly one Pentium, a 200, fail. I have never seen a motherboard fail except after a power surge. Nice thing about PC motherboards is you can hike down the street, pick up a replacement for $100 and be back in business the same day.
I wonder what iMac users will do for a backup monitor while their LCD is in the shop?