I purchased this sleeping bag last week for an upcoming winter camping trip. I was initially skeptical because of some of the reviews I read on here, and honestly didn't expect it to live up to a 0°F rating. At the store, I made sure to open up the compression sacks (which are really great if you're planning on putting this bag in a backpack) to check the stitching and make sure there weren't any visible pinholes that would let the warm air out. The first couple bags I looked at did have these, but the third bag had noticeably less, and I went with that one. If you're looking for a bag for backpacking, this is probably the largest I would go. The bag itself is plenty long enough for me (5'11") to put my feet at the bottom and still fold the hood completely over on itself. The compression sack works really well, and will get this bag down to about the size of a basketball (No need to roll it up, just stuff it in the bag feet first, cinch the bag, push down on the top and pull the opposing straps simultaneously). It fit into the sleeping bag compartment of my High Sierra Titan 55, but it was a little bit of a tight fit (see picture). I put the bag to the test in a section of the Appalachians. Just so you know what conditions this review is based on, I will list them below. I was inside a Coleman Summer Dunes tent, which had the mesh top covered with a single layer of fleece blankets (we couldn't get the entire top covered with the three small blankets, but the gaps were small). The rainfly went on over the blankets, but we didn't stake it open for ventilation. I was wearing an initial layer of Starter compression pants and shirt, two pairs of socks (wicking and wool), jeans, a t-shirt, and a fleece. The temperature on my thermometer read 20°F and stayed between 20° - 25°F all night. I had the hood completely cinched shut (the remaining opening is roughly the size of my fist), and the bag was directly on the tent floor. I was comfortable and warm the entire night. The only problem I encountered was that I was able to feel the the cold from the floor come through the bag. This was remedied by laying out a winter jacket I had brought with me underneath the bag. I had also tossed in a 'Hot Hands' in the bottom of the bag before I was ready to lay down, but I doubt that this attributed a whole lot to the heat maintained throughout the night. Everyone else had normal sleeping bags on this trip and they froze. I was the only one who slept comfortably and the only time I got truly cold was when I had to leave the bag to hand out additional hand warmers and blankets. It was a little chilly getting back into the bag, but cinching the hood, and folding it over allowed the bag to heat back up within minutes. I was skeptical at first, but after testing this bag out I was truly impressed. I would definitely recommend scrutinizing the stitching before purchasing it, but all in all it is a great bag especially for the price. The only thing I would recommend if you are planning to take it out into the cold weather is a sleeping pad to separate the bag from the ground. I'm tagging this part onto the review: As I was taking pictures for compression size reference, one of the plastic buckles on the compression sack broke (so I only uploaded a picture of it inside the backpack's compartment). I wasn't pulling hard, but I would make sure not to overtighten these and to pull them exceptionally slow. I'll probably just buy a new ladder lock buckle to replace it. I took the expectation down to a 4/5 for this alone.