@Mactheknife68, really consider the inner vs outer first question. For longer trips (back/bikepacking & sea kayaking), I find the key to enjoying your shelter setup is not avoiding wet, but being able to manage it.
For me, this means a tent where:
- I don't have to pitch an inner before I can get a "shell" up
- I have enough room to change clothes inside without touching the shell (important for mornings when there is condensation)
- I can keep the bit I sleep on (the floor) dry, even if the shell is soaked in rain / condensation
I also think that with any tent of any design, you just have to accept that you will get condensation in the "wrong" conditions. Therefore its important that you can deal with that condensation. Some things to consider in that regard:
- Can you get to the door zips in the night and get out without rubbing yourself all over a soaking fly?
- If the conditions change from condensation heavy to windy in the night, are you going to get internal rain as the condensation falls off? Personally I have found "standard" tents designed with a US style mesh inner to be really bad in this regard, as the condensation is suspended above you. Tarp tent style shelters with steeply sloping walls seem to be much less of an issue, as a bit of fabric movement is more likely to make the condensation run down the outer than fall on you
- How much space is there between inner and outer. The closer, the more likely you will accidentally contact the outer. I find that "standard" tents tend to be closer than tarp tent style shelters. My Trekkker Tent Stealth is so spaced that its actually hard to accidentally touch the outer when you are inside the inner
I've never used an SMD Lunar, but have thought about one many a time. To me, one of the main challenges with a single wall tent would be packing it up on a wet morning in such a way that when I unpack it at the end of the day, the floor is still dry. My musings have been "can I fold it in such a way that the floor is protected?
Obviously a separate inner / outer tarp style tent like the Dechutes (as others have suggest) + Serenity or 3FUL $40 Net would make the above much easier at the cost of around 200g. With that setup, in dreadful weather, I could pitch the tarp. get inside, change into dry clothes, set the net up without going outside. In the morning, the procedure can be reversed, almost guarenteeing an inner that never gets wet. This is what I can achieve with my Trekker Tent Stealth 2, although as someone else said, the pole is annoying, and its hard to get out of the door when the tent is wet with condensation in the night, which is probably my single biggest dislike of it