I have the MSR Hubba Hubba, however with a little different fly set-up that it came with. I bought a huge piece of silnylon and my wife (the darling that she is) fabricated me a full coverage fly that covers all the way down to the tent pegs(to the ground), so in effect is a two walled tent. It is a little heavier than the Hubba Hubba comes but as light as the thing is, a little more weight shouldn't hurt much and believe me after put together it's a brick in the wall.It leaves a little space between the actual tent and the fly and I think that in really cold temps it does keep a little warmer that regular.. We hike in some pretty cold weather and my wife always likes to experience her handy work too. I am sure that there are winds that could up-root it but so far , it has worked like a charm....sabre11004