I’ve played a few thinlines, as well as owning core and S2 versions of the “regular” 594 - I thought the thinline looked absolutely righteous when they came out, but to be honest, after playing a few, they didn’t do a whole lot for me. I find the maple topped S2 594 to actually hit me like an SG when compared to the core version being more like an LP. The S2 594’s seem to consistently be lighter, probably due to the thinner maple cap and perhaps they use less dense mahogany than the core, too. Tonal balance is a little less low mid punch than the core. The thinline just seemed to lack the top end liveliness for me. Now, I’m not saying they’re bad, by any means, still light years ahead of many other guitars in the price range.
I think the S2 594 range now has the LT version of the 58/15? Haven’t tried them, but I’d like to. I think I would prefer them over the non-LT version.