When I bought my ProStaff a couple of years ago, I fussed & fretted in the store, looking through the ProStaff, then the Buckmaster, then the Monarch, then back through 'em again. I also compared 'em with a Leupold (can't remember which model), and folks, I gotta tell ya; I couldn't detect a darned bit of difference with the naked eye, either with light transmission, clarity, or vignetting (sp?)
I'm sure there are differences detectable with sophisticated instruments, but I won't be using those instruments in the field, or on the range.
I kinda think it's similar to the Great Megapixel Wars in today's digital cameras. 10 or 12 meg, it's all overkill detectable only to the most exacting, demanding professionals.
The main thing is I can see clearly through it, and the little holes always appear exactly where the lines cross
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