Bought these the last time around Woot! was selling them.
Yes, they are very thin. Yes, that makes them quite ‘flimsy’ if you grasp them wrong. Yes, my initial reaction was, “Well, this was a stupid purchase.”
But after a bit more thought and some actual use I realized that they were comparable to some of the best glassware in terms of thinness, with all of the benefits that gives. And in use they do not seem flimsy at all.
I would not suggest them as a replacement for fine wine glasses in most instances, but for garden parties, picnics, house-warmings (my reason for the original purchase) and so forth they should work admirably.