Probably any of the high end scopes over a grand. They all have really good optics. Also keep in mind objective size and power will play a part in it as well.

Do you have a price range or size limitation?

Out of curiousity what do you need it for?

Cabela's carries many of the top end scopes if you want to look at them. However if you are looking for that you will really need to go look at one in person and compare them. Not just take someones word for it or go by what you read on the net.

Paul