I have a Nikon Prostaff 2X7, on my Traditions Pursuit and I had problems w/ it in the begining but Nikon has great customer service and replaced it, no questions asked. No problems w/ the new one. Works great.
I also have a Burris Fulfield II 6X on my Traditions Evolution. I have never had a problem and the glass is very clear. I really like the Burris so I guess it really depends on your likes,needs and budget.
Good Luck Jim