While I don't have experience with the double, my single has worked out very nicely. Extremely quick setup, less than a minute, very comfortable w/ a back packing mattress, and just enough room, with the exception of headroom while sitting, only drawback. As far as condensation on the inside, you will experiance some, possibly more with two people, but if you keep the side doors open for ventilation, it isn't too bad. Only on one pretty damp and chilly morning did I experience any significant moisture on the ceiling at last years rally, but nothin else was wet. The covering case they come with seems kinda cheesy, but so far it has held up well, better then iI expected. The only drawback is it does not include a rain fly as standard gear, such as does the unit that Cabelas offers, but they are also more money, so it is probably even in the end. Overall, I have never slept well in tents for one reason or another, and I slept like a baby for 5 days at the rally last year, so that really sold me on these. The real drawback I see is the closed footprint and weight as compared to a regular tent, but I think the drawbacks out weigh some aspects of conventional tents.
Hope this helps you out, Erin