[Jack]

I don't know of anyone doing objective testing with any sort of scientific method. Wish I did.
I suspect the age old question 'who's gonna pay for it' is the reason why no one's doing it.
I think we've all heard the opinion 'Brand A is the best thing since the invention of the wheel' and 'Brand A is total junk', from one source or another. Part of the problem there is that a lot of brands now have a wide array of scopes at different price ranges. Within the same brand, the low end stuff may be mediocre at best, and some of the higher priced models can be excellent.