My gripe with Super Moonlighters was their bulk rather than anything else. I couldn't see much, if any, improvement in light gathering between a 45, 50 or 56 with any of the scopes in this price bracket. A sharp 4x40 was as bright as any of them, though added mag sometimes gave a bit more definition on target. That ?x50 Tasco was as IJ stated like a 4x20!
Kassnar should have been better than they were.
Now if you had a Leupold, B&L, or higher end European scope then it was as if someone had turned the lights on. But they cost more than the gun and I'd be still doing the paper round.
A JD HW80 combination is something I have thought of a couple of times. Then I pick up a FWB Sport and get over it. He shot a .22 in the field, though his first airgun was a .177 Crosman pump (but that was all he could afford having just got out of the Army; he did some tricky stuff in the troubles. I didn't know him well but he definitely inspired many.) If you followed his writing he started with a .177 for penetration. Then switched to a .22 for rabbit shots into the engine room. By the end he still shot a .22 but generally only head shots. I stuck to the .177 and head shots from almost day one (circa 1978). Now its the norm/expected. The greater part to it all is that modern rifles, ammunition, and scopes can give the consistency and accuracy to pull off these shots in either calibre. In 1980 a pigeon head shot was tricky even at point blank. By 1986 it was doable out to 30m and today possibly 40m and beyond. How things have changed.