I've seen 4 episodes so far (thanks to rosie's vids

In format it's a relatively straight-forward, no tricks beneath the sleeve, melodrama/romance with very little humor if any, in the vein of other K dramas, particularly the Season dramas. Plot devices- childhood seperations, reunions, twists of fate, missed chances, jealous lovers, love triangle - in those shows are in effect here. In fact, if anything, Stained Glass is sort of the updated version of Winter Sonata (they even play piano music from the latter show in one of the episodes -- was this deliberate homage?). But the pacing is much better, and something about the show breathes much better than its predecessors. Bottom line is that SG works. It's not a deeply enriching kind of show, but it's definitely entertaining.