Had the Winter hammock out last night, it was a last minute thing so it ended up strung between the trailer and the climbing frame! My two youngest girls wanted to sleep in it and as they're off school for the rest of the week so that wasn't a problem. We piled them in at about 8pm and they got off to sleep fairly quickly and were still warm and toasty when I checked them at 2:30am (video'd it), went out again at 4:30am and they were gone, talking to them this morning they were just uncomfortable with the two of them in there so they came back in the house, but they thought it was nice and toasty the whole time.
Temp last night was a low of -7 (-17 with the wind)