I have used both a Tarptent and SMD tent. The TT I have is a squall 2. It has fairly good ventilation depending on the pitch. It has weathered a snow storm and heavy rain with no problems. Since the squall 2 is bigger i cant comment on the space, but just the quality of the tent.
I bought the SMD Gatewood cape, which is kinda like a lunar with a hood on it. I liked the idea of the shelter also being rain gear. I really like the Gatewood, you can adjust the pitch to allow more ventilation. Though the tent does take practice setting up, and figuring out how to change the pitch.

Both tents ventilate well but i think the lunar would have more, depending on how you pitch it. The lunar's door faces away fro the wind, where as the contrails you point the door to the wind(?) Though I think the Contrail would shed the wind better, i haven't had any problems with the gatewood and wind yet. For bug resistance the Contrail would win because it has a floor, you can always add netting to a tent. oh yeah i hike in the sierras so ground bugs aren't a big problem.