Although I would never swap my Macpac tent for any other (I can compair a few as my friends have Saunders, Terra Nova, Sierra Design, Karrimor and others), there are a few drawbacks with tunnel tents.
The main one is that they never quite pitch as rigid/taught as goedistic tents so you get some flapping noise on a windy night. Also, because the Macpac Olympus tent is pitched altogether you can't really split the load up (one person has to carry the whole tent).
Saying that, if the weather is going to be rough, we always choose my tent over anyone elses because everyone accepts that my Macpac tent is best in foul conditions, if only because you can get it pitched quickly and guarantee that the inner will still be dry. It will also take an absolute hammering and stay up.
They're expensive but money well spent!.