Yes I have a DRO. It's one of the Chinese scale types but it has worked good for me.
I haven't scrapped any parts yet. Like I said, I've made a few 'errors' but all were fixable. I guess if I was a purist whenever something wasn't 100% I would start over but as anal as my wife says I am I'm not that far along. When I learned my trade I was taught that if something was fixable it wasn't junk.
When doing many hundreds of steps on a project like this the hardest part is maintaining concentration, wife questions, telephone calls, where the hell did I set that tool, etc.