Originally Posted by NOS88

+1 to all TSL has said.

Just with tube selection alone you're looking at diameter, gage, special shaping, etc.

I've got some really, really nice road bikes, all fitted correctly. But the custom built one suits me better, in that, it does what I asked the builders to make it do. After over 1500 miles with it (only got it late last fall), I can say going the custom route really did make a positive difference for me. I'll concede I could have "made do" with something else, but if I could swing getting what I really want, why "make do"?

The key is picking really good builders, knowing just what you want, and being able to convey this to the builder(s). If I had the experience that abqhudson had, I'd be very unhappy.