The only round one guy I've whiffed on was Crabtree, I've missed a couple that I incorrectly doubted (Stafford and maybe Cam stick out) but I've avoided a lot of landmines in guys like Moreno, Beanie, Sanchez, etc. Only about a decade deep in this game though so I can't reach back too far.
EDIT: the reason I'm just focusing on the last few years is scouting isn't the same now as it was a decade and obviously more ago, in this age if you whif it's real bad given all the info available and $ in the business. It was easier to miss on these things the longer back you go.