Yea, I think this holds true for non-specialty machines. Be it for gaming or anything else besides general use, you wouldn't want to get a bought machine. For the people who are looking to build a sub-$600 machine, they would be going with the lower end parts anyway. It's the people building the $1500+ machines that are going for the "enthusiast" market. My machine would have costed about $8000 if I bought it from Dell or something... So of course I built it myself.
Tas.