Interesting comment about the JAB white shirts. I'd be interested in seeing which shirt you're talking about specifically if you could provide the link. I'm always hesitant to order white shirts online because I hate the translucent look that plague so many of them.
The sales seems to have ended. I paid half price for mine, but I'd imagine, in true JAB fashion, they will be on sale again within the next couple of days.
The shirts are new, so they aren't in stores yet (I called 5 stores near me). I'd expect them in stores within 2 weeks, though. I really dislike thin white shirts, so that is not really a concern with these. They aren't as thick as some super-heavy fabrics, but I've seen much thinner. I actually returned a BOSS black label slim fit because it showed my tattoo on my left arm - it was that thin.