Seems as though if the rest of the competition were to offer a form of rainguard they would say so.........so go out and get that Bushnell and you won't be sorry.
p.s. If you care to try it, there's a product on the market called "RainX" that works well on windshields and such. However, I don't know if it would be safe on scopelenses with anti-reflective coatings......Your choice! I know the product contains alcohol.
Jim