Bob, I think I have the same 3.5-10 x 50 Kahles, I had the idea a couple of years ago to send it back into them to put a #4 in it, while I like the #4, for some reason it does not seem as bright as it did before, maybe just my imagination.
but as you say "dark is dark"
a VRL-1 with a green diode is a great light, I also have the more expensive Wicked Light with a red diode but don't like it as much.
in my finally learned my lesson at a late stage in life; unless your going to buy a NV scope a good reticle in a 25 mm objective with reasonable coatings will get you as far or further than a target reticle in a 50 mm objective.
To your point regards your Z6, my Victory HT 1.5-6 x 42 with #60 IR is not too shabby the illumination is done well I think at this level.
