Originally Posted by thenathanator
I guess the main thing is that I feel like I've built a bike which is less reliable and more expensive than a Mark V would have been.
I guess the best way to look at it is not in economic terms... but education terms. You've learned a lot from building up your own bike, and will continue to learn much. As you learn more about bike mechanics, you'll be able to build a more 'reliable' feeling machine, something you wouldn't have gotten from buying a pre-built bike.
That said, after three years of cobbling together my own fixed gear conversions, I'm just about to order a Mark V frame from IRO and assemble it myself. Similar outcome, but the joy is in the path you take to get there.