Yeah, mostly you get to choose where the money's spent,,which means better components all around with better warranty on all the parts than the standard 1 year.
It isn't very difficult to build, there's a sticky on the basics. And a lot of help around here, including helping with the specs.
For $700 you could get a nice AMD system with newer chipset mb, an x4 cpu, and possibly a 6950 gpu.
What country are you in so we know where you can buy from,
and are rebates ok to factor in?