Looking good! I'm gonna assume that that first pic is the GSC. Is that right? Judging from the kind of, uh,"light" yield so far, it looks like GSC. I like the way the WW is looking, though. And I like the way the GSC looks, too, just seems like it could maybe fill out a little more.
As far as when to tell when to flush, I dunno cuz I don't flush. How long's it been since you induced flowering again? Can't remember off the top of my head, but if I were you, I'd let 'em go a little longer. The GSC especially (if I'm assuming correctly that the first pic is the GSC) looks like it could fill out a little bit more. But maybe not.
I bought a jewelers loupe to check my trichs, one of those ones with a light on it, and I found it kind of useless. The light just illuminated everything, made it impossible to differentiate between clear/cloudy/amber. It just made everything glow haha. I dunno anything about growing either GSC or WW, but judging from the pics, I'd let them go a little while longer, if for no other reason than to see if they maybe bulk up a little bit. Those are some FROSTY motherfuckers, though haha! Reeeealllyyy looking great.