I've used tunnel tents for the past 15 years, recently purchased a new Hilleberg Nammatj 2 GT to replace my aging 15 year old tunnel tent, there easy and quick to erect, my old tunnel tent is very similar in design to my new Hilleberg tent, the Hilleberg is superior to any tent I've ever owned and probably ever will. A true palace in the bush, snow, beach or where ever you wish to pitch. With my new found interest of long distance hiking, to own a tent where you can erect the outer tent first in a matter of minutes in the rain than unpack your gear undercover away from the rain and erect the inner totally dry is a real luxury. As you can guess I'm very happy with my Hilleberg tent.
Tunnel tents are also very roomy for there weight. One of the main advantages of a tunnel tent is that it is very easy to pitch. Its pitching time is very short that you would find it hard to believe that you were able to finish it in just a few minutes.
Hilleberg has a section on the difference between tunnel tents and dome tents,
http://www.hilleberg.se/products/tent_g ... el_or_dome