A few remarks about the Meopta S2
I don't have the lab equipment to measure transmission, but I have tested the S2 alongside a Swaro ATX 95 pretty thoroughly and extensively, including side-by-side outdoor resolution tests with the Swaro stopped down to 82 mm to eliminate aperture differences. Throughout, my impression was that the ATX was marginally brighter and had slightly more vibrant and realistic colors, so I would doubt that the S2 would measure higher in transmission tests. It is possible that Meopta's transmission figures are for the scope without eyepiece, in which case the total transmission for scope/ep combo would end up somewhere in the 85 % range, but this is speculation on my part.
In any case, the Meopta is plenty bright enough and in practice the equal of any comparably sized top scope in this respect. As an aside, I feel that the importance of light transmission percentage has been exaggerated on this forum lately. I'm very happy that Gijs has been doing his lab tests and posting his results, and find them valuable and reliable, but since it is the only significant optical parameter that gets objectively tested, it gets more exposure than it needs. For spotting scopes, having an aberration-free sample with very low CA is more important, and for this reason a Kowa 883 is going to give better real-life performance than any 80 mm Swarovski or an 82 mm Leica, for example.
But I digress.
Back to the Meopta. All the S2 samples I have seen thus far have been very well corrected and given a sharp image up to 70x. In my view, it is the best under-85 mm scope currently available. Both zoom eyepieces are fine, but the AMD "feature" Mark mentions with the 30-60x zoom is definitely real. That eyepiece has incredibly wide FOV at 30-40x mags, wider at 30x than any of the fixed 30x wide-angles, including the Nikon 30x DS. But the way they got it without compromising eye-relief is by "squeezing" the edges at the low end of the magnification range, hence the AMD. But since the view is sharp to the edge, the view is eminently usable throughout the field of view and throughout the zoom range.
In still ended up liking the 20-70x zoom better. It has equally good eye-relief to the 30-60x, is also sharp to the edge throughout its range, is very easy to view and offers acceptably good fields of view and excellent sharpness all the way to 70x. The magnification range is just about perfect for an 82 mm scope, and it won't make you dizzy while panning. Whether the wide zoom will depends on the user. I was not overly bothered by it, nor was one friend of mine who hates "rolling ball" in binoculars.
With either zoom, the Meopta would be an excellent choice.
Kimmo