I started Airstreaming two years ago in an 87 34'. With the proper TV, it tows great. I remember asking the same questions when I was deciding on mine and I remember someone on this forum saying, "it tows just like a 27', the extra 7' just follow the first 27'.
Many who have towed them as well as shorter models, say the 34' tows better than any of them. I just traded up to a 98 34' widebody with a Hensley Hitch. I had wanted a Hensley, but had not put out the $ to get one. It came with the rig I just bought.
My wife and I would not have anything other than a 34' for the space and enjoyment it provides. I run into more people who say that would like to have more space than people who want to give up the 34' for smaller quarters. It is really though a personal preference. I would not let towing be the central issue my my decision however.