I just bought the GC, and have the nettent on order --- when I called a few days ago they had the cape ready to ship, but told me that the nettent would be about two weeks out. I was quite pleased to get the GC literally the day after I ordered it (I live in an adjacent state which likely helps), and they won't charge my card for the nettent until it ships.
Anyway, all I have at this point is initial impressions; I walked around briefly in poncho mode and setup and seam sealed it as a tent.
I liked someone else's suggestion to get a very light (look online for "disposeable") poncho to use in camp if significant rain is anticipated --- or indeed, pick another shelter, as this is floorless. I got one of these from my wife that weighs 1.7 oz, less than 1 mil thick. Seems perfect for trips/situations where you need or want to move around camp in rainy weather.
Anyway, weight: 11.1 oz as shipped (counting various cord/harness, not counting the terse instruction card or plastic bag that the cordage came in) --- i.e., dead on accurate. Of course by the time I add in 6 light stakes, a polycro ground cloth, and seam seal it, the total weight (without net tent) will likely be about 15 oz. Then add 7 oz for net tent and it's 22 oz, but for shelter and raingear.
Using it as a poncho: The ventilation is in the front, none at the sides; I like it better having ventilation on both sides. In particular if it's raining hard I'd be happier having the sides open than the front. I’m concerned that this will be significantly less ventilated than a normal poncho, and hence that I’ll sweat in it too much; TBD. I live in WA state where raingear is something that doesn't just get carried, it gets *used*, so this is obviously significant. I saw a variety of reviews of the GC, but very little on the raingear aspect of it.
A cord around waist works to help keep it under control (I do this with an ordinary poncho), but in order to have enough fabric above that cord to move my arms enough to use trekking poles, I end up with less coverage of the front part of my body below the waist as I do with a normal poncho; crotch is covered and upper part of upper legs, but more of the upper leg down to the knee is exposed to wet vegetation than with my normal poncho.
To put it another way, for me a normal poncho is sort of a well ventilated rain jacket plus pack cover plus rain skirt all in one. The ventilated part and the rain skirt part both appear somewhat compromised here, but again --- I'll only confidently talk about this after I've walked with it for a while in rain.
The pocket in front is nice, though as designed it sits on the inside of the cape; not a big problem as the large vertical front zipper is right next to that, however. This could be helpful for things like maps. In general it's sometimes a problem accessing things in a poncho that are normally ready to hand and this should help --- both the pocket and the long vertical zipper in front.
Note that to solve the length problem it’s important to connect two loops on each ~side up inside the poncho lest they drag. I'm about 5' 10" and don't anticipate any drag-on-the-ground problem.
As a tent: Brilliantly designed; went up well the very first time. Seems to be a good amount of room inside, and I can sit upright in the middle (and for my height I'm tall in the torso). Using second pole either externally or (perhaps, haven’t tried yet) internally to push out tent wall a bit is a good idea too though not essential. No issues here, or at least that I’m aware of. With the net tent or with few bugs out, this will be a great setup. My only concern is high wind with rain, or literally water flowing through my camp site (the rare case where a bathtub floor is worth having). As Ron Moak says, good site selection is important there.
To address inside room from a different perspective, my solo tent is a tarptent Contrail, which is very roomy for a solo tent. I don't feel constrained in the GC, however. Unlike the Contrail, I don't have to shift around a lot to sit upright, nor do I have to hunch or crawl to get to any end/edge of the tent.
I think that to be happy with this a person shouldn't think of it as a floorless tent, but as a light tarp with excellent coverage! Expectations are everything. My next trip starts Wednesday I'll likely be camping by a lot of lakes (likely buggy), so without the nettent in hand I'll reluctantly go with my solo tent, but I'm really looking forward to using this on some trips.