Before purchasing the M845, I tried a much less expensive scope with Gen1 technology. I know it's apples to oranges, and it really is the difference from night to day. Although the the Gen1 was useable to 50 yds or so, it was foggy around the edges, had a grainy picture, and was very heavy. However the worst part was that no matter how much moon and starlight I had, the Gen1 would not give me a useable picture without the use of an IR illuminator which was visible to the naked eye. No good.
I returned the Gen1, sucked it up, and bought the M845. Good grief. I still have the black and green picture, but it's very clear. There is no fog around the edges, the sharpness of detail is just amazing. The M845 is actually lighter than then Gen1 and you can actually get a comfortable position looking through the eye-cup of the M845, unlike my experience with the Gen1.
The scope is built solid and you can tell it's made well, unlike the cheaper Gen1 I tried previously. I also like that it takes 2 "AA" batteries, easy to find and replenish. I believe the manual says you'll get about 40hrs of use out of the batteries.
The best feature of this scope however is its light-gathering abilities. I had purchased an IR illuminator to go with the Gen1, so I kept it for use with the M845. No need. I've used this scope on the most overcast nights and I don't need the illuminator at all. Here's my best illustration for how well I can see with this scope:
I have family with some property and we had taken it out into the front yard area which is a few acres, a mix of open areas and woods. One night I had sent one of our party about 50 yds straight out to crouch down and then hold up fingers, so I could test to see how much detail I could make out with the scope. Shortly after he crouched down, I'm looking at him through the scope when he stands up and starts walking towards me, pointing off to his right.
I could tell by the way he was pointing he was actually pointing at something like he was worried about it. Just then I remembered they had experienced some trouble with break-ins recently in the area, and thinking the worst I swung the scope towards the area he was pointing at.
We had 4 people standing out there, and all of us were looking in the same direction. It was so dark out they could not even see a silhouette, but my friend had briefly seen a flashlight light up off in the distance, which is what prompted him to point.
Quickly scanning through the M845 I instantly saw a man walking our direction, still a good hundred yards out. Even better I could clearly see the unlit flashlight in his right hand, and what clearly was a firearm on his hip. I also recognized the man instantly as my father in law.
That's a lot of detail from that distance, with cloud cover and no IR illuminator. If it had been a threat I would have seen them a long time before they saw me. I'm very happy with the purchase of the M845. The only negative thing I can say about it is that it's ugly with that big box for a body, but it works beautifully.
Pros: visibility, lightweight, simple
Cons: ugly...that's it
This review was written in the old system and had content requirements that are different than reviews written today.