My DMR is set up in a similar manner as you describe for your "urban sniper" rig, it's definitely more precision oriented with a NF 2.5-10, Geissele trigger, and heavier contour WOA barrel. Using 77 grain match it's pretty wicked out to 600+ and even with M855 I can pretty consistently hit a IPSC silhouette at 600 yards.

I like the TAC30 but part of me wishes they still made the FDE version though.