I seemed to think they found the modified Skyline the quicker car even though it had less kW. They also point out that if you want to modify your car then the Skyline has more potential.
I think a better comparison would have been a manual Skyline with suspension, exhaust and tune up against the same for the XR6T. The first round comparison the XR6T was a manual whereas the Skyline was tiptronic both times. The Skyline coupe also produces less roll then the four door variant which would have played a part.
I personally like both. I like the practicality of the XR6T as it has four doors & good low down torque, but it is a heavy car. As an everyday driver I would take this as they are a very easy & comfortable car to drive.
If I wanted to do some track work occasionally, modifcations and wanted the better looking car I would take the R34GTT. I suppose the absence of 2 doors on the coupe doesn't matter too much as I wouldn't be sitting in the back anyway Or you could just get a 4 door.
Whichever it was I would go for a manual though!