When I purchased my range finder I was lucky enough to be able to try out a few different brands at the same time, side by side under field conditions.
In the end, there was very little difference between the ranges given by each type other than some crapped out far short of the distance specifications on their containers and in advertising.
Lots of things will effect just about any range finder from mirage to snow to rain or fog. The next issue will also effect the reliability of the unit and that is the class level of the laser itself.
There were two things that finally influenced my decision on which RF to purchase. The first was the class of the laser. It needs to be a Class 1 designation if you need accuracy over distances of 300 - 800 meters.
Most range finders are not designed specifically for hunting. They are designed for sports and even checking boundaries in a relatively loose fashion.
OK, I settled for a Swarovski LG model. Why??? First, it was rated out to 1500 meters and if the atmospheric conditions were suitable it did so reliably and it has a Class 1 laser. Secondly, the monocular has a 7X rating with a 32mm objective lens that lets in as much light as a similarly rated binocular/monocular with the same lens. The other thing which was also very important was the diameter of the "Ocular" lens or the exit lens. Science tells us that our eye can only utilize a 5mm Ocular lens and anything larger just isn't needed. OK, fine. What the manufacturers don't tell you is that your eye has to be perfectly centered on a 5mm lens to take full advantage of its capabilities. This situation can be a real pain in the butt and makes it necessary to carry an accompanying set of binoculars to view an area. All of the different types of RFs I checked out had 5-8mm Ocular lenses including the Leica. The only RF that had a larger 15mm lens was the Swarovski.
The Leica and Swarovski had very similar range finding abilities out to 800 meters then the Swarovski just kept going under similar conditions. The Leica/Zeiss were much more difficult to get on target as well. The Burris/Bushnell/Tasco and one other were undependable after 500 meters. All except the Swarovski had IMHO poor light transmission qualities when it came to their optic.
That was about 12 years ago and the Swarovski is still doing its job reliably. Depending on the type of hunting I do, I will often leave the Zeiss Binos in the truck and just use the excellent optic on the Swarovski RF.
I can't comment on the Sig Kilo because I have no personal experience with it. I have however matched my RF against later made offerings and nothing seems to have changed. There are legal limits as to how precise the LRF system can be, or at least that was the case when I purchased mine.