If you're having "tunnel vision" you need to bring the scope back farther. Too much "relief".
Nikons already have very limited eye relief. Moving it back closer to your eye still results in a black ring about twice the size of a Leupold.
Nikons Prostaff and Buckmaster have good clear glass for the money, but it is the other features that are deal killers for me. Very limited eye relief, tunnel vision, and heavy. I've got a couple of Monarchs that are much better. While the Nikons aren't a bad scope, there are better choices in the same price range.
If someone is looking at a scope in that price range the Redfield is a far better choice. If you buy a 2012 production Leupold VX-1 you are now getting the best $200 scope out there. Leupold upgraded the VX-1's and VX-2's for 2012 and they are now far superior to anything in their price ranges. My new $330 VX-2 is a better scope than a $700 Zeiss. The $200 VX-1 is very similar to a 5 year old $400 VX-3 I own.
Their reputation for toughness doesn't hurt either. I've abused several for years with no issues. Can't say the same about any other brand of scope.