Pro-Staff are really nice scopes (for the money, I still have one) - and I've heard Nikon warranty is solid.I was REALLY impressed with the Prostaff for what they cost. $150, 4-12x40, Mil-dot Reticle. It was a no brainer for me after having a 3-9x40 BDC Prostaff and the price point.
With higher end scopes you pay for a few extras - unfortunately in optics small steps are very expensive; and then there "needs" and "nice to haves".
I couldn't confirm or deny that Weaver-brand bases were "1913-spec".If you are looking at using 1913 Picatinny rails I recommend the Weaver 20 MOA base.