MSR Mutha Hubba tent
Well, I should first admit that I haven't had a huge amount of experience with modern tents, so am hard pressed to compare this tent to others available. However I bought one of these almost two years ago and used it extensively through 2008 on a 6month ride, plus now and then since.
Firstly the physical side, it is a great two person riding tent. It has vestibules in both ends (both the tent and fly are identical end-to-end), and we fitted our panniers and riding gear in one end. I'm 6'5" (197cm) and can just fit comfortably at an angle across the tent with space for my girlfriend, plus Camelbaks and clothes bags inside too. There's also decent space to sit up inside.
It worked and kept rain out too. Not too sure what more I can add there. It is simple to set up, and we never needed guy ropes, just pegged it out, even in reasonable wind. A downside is that it can't be (or at least I never worked out how to) pitched fly first.
The zips got a little temperamental after a few months of use, but a bit of silicon spray brought them back to life.
So all in all, I was and am very happy with the tent. And in my mind is a perfect size for two motorbikers. Afraid I'm a little thin on weights/lenghts/etc, but Google can uncover that for you.
Vladivostok - Denmark 2008... Finished.
Denmark - South Africa 2010-2011... Finished.