Ay dunny , I just finished a two day camping trip. It was a high of 34 low of 22.
The morning and days weren't bad because of hiking and being active, I had on thermal underwear a pair of pajama bottoms and cargo pants a white t, thermal top hoody and a coat ( I didn't even wear the coat I was hot.
At night in the tent I had one of these
First night I had it on medium and high cause it was my first time ever using it. It was hot as fukk in the tent. The ground was cold because I didn't bring a cot or air mattress. Everything else was fine. I changed tanks 3 times. On med I got about 5 hour's, then I changed it and put it on high and got 1-2 hours then I changed it again and put it back on medium.
Next night I just used low for like 9 hours.
Sears and kmarts are closing see if you can cop the big one under $100 like I did, consider getting a tent.