Lots of people on the PCT (Pacific Crest Trail) are using these kind of tents – including myself (I recently completed 560 miles). Many ultralight backpackers use a tarp instead of a tent and swear by it. That can be tricky to set up and doesn’t keep all of the bugs off. The tarptent concept is based on the simplicity and lightness of a tarp, but made into a more traditional tent look. While Sierra Designs’ one-person tent looks good, it weighs 2lbs 11oz. My Contrail tarptent is 24 oz. It’s a single layer silnylon tent with a ground sheet and mesh all around the inside between the groundsheet and the tarp, top. (Models are available with sewn-in floors or floorless; the latter is $30 cheaper and lighter.)
I use my trekking pole as the main upright. Set up took a while to figure out, but now I put it up and down in much less than 5 minutes. I can rig it for strong wind, too (it’s designed to be storm rigged in need). It’s great for the Sierras, but wouldn’t be so suitable for wet climates. If you camp somewhere moist, like near a river, it can suffer from condensation. As such, I have learned to camp differently and now leave the door wide open all the time apart from the mosquito net. It hasn’t rained much in the 2 months I have been hiking the PCT, but when it did, the tent was waterproof. You have to seal the seams yourself, but it is very easy to do so. The only modification I have done is to swap the standard 2 rear pegs for 9 in. ones, which work better especially in sand.
Ultralight backpackers also frequently use a sheet of Tyvek as a groundsheet. This is the material used as a vapor barrier in house construction and as sails for boats. It is breathable and water-resistant. I could only buy lengths of 165 ft. in Home Depot, but you can often pick it up at construction sites. I use my Tyvek underneath my tent for added protection (which is redundant overkill really) or if I am cowboy camping just under the stars with no tent. I also have it handy in my pack and pull it out whenever I rest — it’s really nice to sit on and it keeps the ants off (a little). It is VERY lightweight and very tough. Some backpackers report theirs having lasted 3 years and going nice and soft in the washing machine. The only thing I have heard of that is lighter or stronger is spinnaker cloth, but that’s expensive. Tyvek groundsheets are $12 via Tarptents. If you are going hiking and need a small piece of this stuff just call Henry at Tarptents — he sent me a bit whilst I was on the trail.