I used a tube tent - once - in the North Cascades in an October sleet storm. The problem with them is that any water that gets in them runs to the low spot, under you, and gets picked up by anything absorbent (eg. sleeping bag, clothes etc.). Condensation inside can be fierce and unless the ends are open (to storms and rain splash) you will get condensation. I guess you could let the water run under your sleeping pad but that didn't seem to work for me. Two of the more memorable nights that I have spent. <img src="/forums/images/graemlins/tongue.gif" alt="" />