I have the Lunar Duo and my wife and I fit great inside it and we like it (I am 5'10" and 200 pounds, she is 5'2" and 90 pounds). I have only used it about 5 times though with both of us in it. I have used it a few more times just in the backyard or around home by myself. Condensation can be an issue, but it can also be dealt with just fine. The biggest thing I had to get used to with the LD though is the way the floor moves. It literally hangs from the ceiling and being that it is silnylon, it will slide across the ground sheet pretty easily. Meaning, if the tent is pitched on any sort of a slope (even slightly) we will wake up in a different spot than we started. What worries me about this is that I don't want to wake up and find that the floor has torn away from the ceiling. One thing I did to fix this was to paint some silicone dots and stripes on the outside bottom of the floor. This has helped a lot.
Here is a little write up I did on my LD when I got it:
I do like the Haven, although I have no experience with it. I love that it is double walled, and I like that I can pitch it however I would like. Maybe just the net tent, or maybe just the tarp, or both. Also, since it is 2 pieces, it is super easy to split up the weight with another hiker (the tarp is 18 oz and the net tent is 14 oz).
If I were in the market right now I would really be focusing on the Haven. It is about a half a pound lighter, although it is about $40 more. As far as livable space, the Haven is only 6" narrower than the Lunar Duo (and considering the size of the Lunar Duo, I don't think 6" will really make a difference).