My four season plus 1991 Stephenson's 2R tent has an integrated fly and tent body. It only needs three stakes for quick set up. Setting up in a rainstorm is not a problem if necessary because all surfaces are coated nylon. Great ventilation and 42 square feet of space weighing only 3#12oz. The new ones weigh 2#12oz. Squamish winds do not bother it either.

I started using a single wall Tarptent Virga in 2003 for the Divide Ride mainly to reduce equipment weight. The Virga saved me two pounds over my 2R tent and performed admirably in all conditions except blowing dust. Simple to setup in the rain without rain inside.

I am now using the Tarptent Contrail. Same ease of setup in all conditions with more headroom.

The latest light weight tarps [less than one pound] can make for a more comfortable camp site in the rain with a small weight penalty. No need to be restricted to the tent only during extended storms. They are also a good backup if your tent should start leaking at some point due to damage or wear.