I have the Mist overmitts. The weight was pretty much dead on as advertised. I cut off the little connector plastic pieces at the wrists, and in size medium my pair now weighs 31 grams, or 1.1 oz.
The fabric looks and feels a lot like the stuff that the driducks rainsuits are made of (I think both prolite and GG sell these rain suits).
Like the driducks, I think the durability will be low on these. My particular concern is using a trekking pole with them, that they'll wear out at the inside base of the thumb or some other contact point(s) with the pole handles. If you're not using your hands a lot they might be an excellent choice.
I've not yet had a chance to use them in lousy weather — or in fact, in any weather — they only recently became available. So apart from weighing them, the above is just direct observation and speculation at this point.
Unless the sizing scheme gets changed, I would size these up from what the measuring chart suggests — I normally wear a size large glove, according to the original ULA sizing guideline (on the web site) I ended up buying size *small*, as that listed the size small dimensions for hands up to (H) 7.75" x (W) 4.5" — my hands fits within that. The mediums fit well enough, small is too small for me, though they might change this based on customer feedback (dunno).
Brian Lewis