When you get to the SLC series, the jump between grades gets way smaller. I have looked at the same deer in South Texas through my SLC's and the rancher's EL's, and he got maybe a minute more visibility in the treeline than I had. If I had not already known where the deer was, I might not have been able to find him.
He did have an older pair of Zeiss 15 x 56mm that were unreal, but not very handy. Weighed more than double my Swarovski's.
My buddy grabbed the EL's and looked thru my SLCs side by side. The only difference is in the edge of the glass
If you read the specifications for the SLC and EL binos, the light transmission values are the same. The difference is the coatings on the EL binos provide better clarity at the edges and a flatter field of view.
One thing about the field flattening that is curious is it has a negative effect on approximately 5% of people. It's called the rolling ball effect and it can cause these people to get nauseous. If you are considering the EL binos. It's a good idea to spend time looking through them to see if you see this effect. If you do, buy the SLC or pony up the extra $$$$ for the NL Pure binos.
There are a lot of good binos on the market. Swarovski is the top of the Alpha league IMHO and the opinion of many others. If you want to learn about binos, read reviews on bird watching forums for the best comparisons.
If you are judging binos only by light transmission, you are not making good choices. A cheap 8x50 bino may have good light transmission values but if the clarity sucks you won't be able to see at last light.
