Agree. that looks like a good deal and a great starter bike. You might want to ask how many miles on the drivetrain. Other than that, fit is everything. You will have some money left over for accessories, too.

As to building your own, thats great as a second bike, imo. You'll need something to ride while you spec your build. And also to make sure you are truly enjoying the white-line riding befiore you spend money on parts. Buying complete bikes is always cheaper than buying all the parts separately. But you knew that ;P