I haven't seen S glass in a long time... I got a bit of it from Bill Howland when he shut his bow building down, and still have a few sticks on a shelf... It's nothing like Uniweft. It's a vertical lay up and It's transparent with a yellow tone to it, but not what you would call clear.... I tried some over veneers and it came out kind of foggy looking. Ended up painting the limbs.
It really kicks up the draw weight compared to gordons E glass. But.... It's also heavier in mass weight, so performance was mitigated .... I don't know whether they even sell it any more.
Kirk