+1
I've not built a bike from scratch, but there are few components I have not replaced or disassembled myself. You become one with the bike. You get to know the bike intimately. Adds enjoyment to your riding no doubt.

It's like the difference between a guy who built his scrappy Harley Davidson from scratch versus the businessman who bought his and knows jack **** about it. Who's gonna win in a fight? Yeah that's what I thought.