oh there are many that wont take you on on the 6x42 however those who really do get out and shoot for real ..... i have bigger from the same but it really doesnt improve having a bigger objective unless you want to shoot 8x . One time my self and a mate tested the 6x42 and 8x52 side by side and performance seemed equal other than the slight extra mag ( that honestly means nothing at unilluminated range under the moon ) .Have a look at what Germam hunters have been using for decades. They have not been allowed to any artificial light, image intensifiers and shooting aids. But a good proportion of their wild boar are shot after dark under the aid of natural moonlight.
The German 6x42, 7x50 and 8x56 with a 4A reticle were all designed for this job. The thick heavy outer reticle posts are particularly important. As described to me - stick one in its bum, one its nose and one up the foreleg and squeeze.
Non of the faffing with red dots, batteries etc etc.
And shooting deer at last last light. My big challenge with this is twofold.
1) can you see enough for you to be certain of backdrops etc etc. appreciate that in many instances you will have been watching the same area and know your safe fields of fire.
2) many deer can and do run after the shot. At last last light, by definition means that you will be doing all follow up and dragging etc in the dark.
For me the best low light scope is a S&B 6x42, followed very closely by a Zeiss 6x42.
I woulnt shoot deer like this but especially under the moon on fresh cut summer hay its been effective . Needs enough moon to cast a bit of shadow really . Its not too common an occurrence and its a total WFT under a dark moon.