Has anyone used any of the Burris Fullfield II scopes in the field? Everyone I have talked to has only taken them to the range and they say they are happy with them. Do they hold up as good as a leupold? They seem to have a nice bright sight picture (in the store) and they have their own ballistic holdover marks for a lot less cash than a leupold. Like I said, just wondering if they are as rugged.