The condensation is really only an issue in the morning and IF you don't have a liner. Invest in the liner - it's worth every penny. When the stove is going or when it's a dry day, no issues. Once the liners in, condesation is a thing of the past! As for size for 2-3 guys, I'd definately go with the 6-man. I have the 6-man with a med stove and it's perfect for 2, and no problem for 3 (and all your gear). The only time I've gone with 4 is with me and the 3 sons (12, 10 and 8 yrs old) when we flyfish in Idaho in August for a week and we can do it, but they're not grown men.
Also with the 6-man, I can stand up in the center (watching out for the pipe) to get dressed which is a real bonus, and I'm 6'3". Anything smaller for 2-3 guys would be a bit cramped especially if you have to spend much time in there (weather?).
The 6-man with liner and med stove is just around 12 lbs total, and divided up between 2-3 guys, that's only 4-6 lbs per guy. Not bad for a bomb proof, heated shelter you can pack into anywhere!
If you haven't seen any in person and would like to see the 6-man sometime, PM me and I can set it up and show it to you if you're ever up this way. I'm in South Everett area and for that kind of money, it's nice to get your hands on something to check it out in person.
Several of the local guys that have Kifaru gear, get together for a wilderness "rondy" in July. The owner of Kifaru, Patrick, flies out from Colorado and joins us. It's a great way to see tons of great gear, Kifaru and otherwise. Do as Tim has said and check out the Kifaru forum for TONS of info from some really experieced guys.
Good luck.
Jim