There is a HUGE difference between their $9.90 "premium" t shirts and the $5.90 dry package ones. Night and day. No one should be buying the $6 crap. Not just the thickness of the fabric but the cut/fit is so much better. I don't think they should even sell the $6 ones as they reflect so poorly on the brand; couldn't believe how bad they were.
The premiums are still relatively thin but much better quality and sort of like the AA/woot shirts except a bit slimmer it seems.