I bought 5 pairs of Sigs - 10x30, 16x42, 18x50 (2 pair) and 16x50.
For me, the pros were absolute junk in 2 out of 3 that I bought, and only one slightly matched the resolution in my Gen 2 16x42's.
Low light is a bit better in the 50's, but they still suck and all pairs are capable of ID'ing game well after legal light. My RF binos are still better than all of them and I still have to carry those so low light was not a consideration for me.
The pros are $600 more, worse resolution, heavier, require more batteries, and I greatly prefer the Gen 2 stabilization. Save your money.