Here is my opinion of the scope breakdown
USO - not an option, glass is terrible for what you pay and I have seen more USO's go down in competition than any other scope.
Nightforce- tough as nails and so-so glass, tracking is always spot on and if FFP isn't somthing that Intrest you in would defiantly take a look at these. The ffp F1 is a nice scope but i think it's outshined by alot of the competition.
Vortex- the razor line is a great scope from a great company, there warranty is second to none if you ever have to use it. They can be had used for around $1650~ and are a good Baffin for that price.
IOR- beautiful glass and that's about it, don't see any around the tactical shooing comps becuase of reliability issues.
S&B - One of my favorite scopes, glass is awesome and tracking and durability are one of its strong suits. That being said I would not buy a new one, they have raised the price and dropped the lifetime warranty and went with a 2yr. No way I would pay $4k+ for a scope with a 2 year warranty. The older PMII 5-25 one of the best of the best and carry the standard lifetime warranty.
Bushnell- the new bushnell elite DMR and XRS scopes is one of the best values out there. Alot of shooters are switching to bushnell for the retical selection and total ruggedness and tracking of the new line of scopes. IMO the bushnell XRS is is THE best value out there for scopes @ $2k.
Leupold- finally starting to catch up with technology of today's shooters. For the longest time leupold relied in the MK4 line and was not willing to upgrade while other compmanys passed them up. The new scopes in the leupold line seam like quality products but for the money I think they get outshined by the competition.
I would also give a serious look to the new kahles 624i and the Steiner tactical series. I will give the edge to the kahles as far as features and glass but I don't have enough time behind either to give my full opinion.