I have been considering buying a military poncho liner for a TQ to use down to around low 50's. Are these things really that warm? They don't seem very substantial weight-wise. Since I usually car camp using a Clark NX 150, weight isn't much of a factor, tho the idea of going for a walk in the woods is still interesting. So I'm torn between the army wool blanket that I have or a poncho liner. Any input would be appreciated, thanks.