I have nothing but good things to say about the 4200 series Bushnell scopes. I would say that they are in the same league as VX-II leupolds and Burris signature line. I must have a half a dozen 4200's and never had a problem with any of them.
For stationary varmint hunting perhaps a 6-24 might be better. For a walk around varmint rifle a 4-16 is about perfect, depending on your terrain.
Bright, excellent quality, clear, and a good value for the money. You will do well with one.
There are many better scopes but you will have to really up the price tag to gain a small amount in terms of brightness and clarity.
Nikon, Burris also make nice scopes in the price range you are looking at.
The VX-II leupold is a great scope and excellent quality. You'll pay a bit more but they are worth it. The top of the line leupolds and german scopes are fantastic but you may have to mortgage the house for one...