I am not about to read all responses, I'm afraid, but I will offer you what advise I can having done a 2-up trip. Sorry if it's already been said.

Initially we went with the same design that you specified and got a 2 man geodesic tent from Robert Saunders for our 2-up overland trip in South America. It was free standing and had two entrances, etc. It performed very well, but space was a premium. Basically, we never needed the two entrances and I doubt you will either when you get in the swing of things. When you pitch you will do so with one clear point of entry and exit: you don't end up needing the second one. You might once in a while but it's really not that essential.

Then, about 18 months ago, we got a dog and if the 2 man was a bit cramped before with all our kit, now it was ridiculous. Our solution was to buy a tunnel tent.

It weighs and packs down the same as the 2 man, but it is vast. Admittedly, only one entrance, not free-standing (you need good tension on the two ends to maintain the form) and probably not as solid in strong winds (but that is only relative: it does not mean it will collapse if you sneeze on it, either).

However, the atrium area is huge: as big as the sleeping area which, in turn, is already bigger than the geodesic. We have not used it in very demanding conditions yet, but we met other tunnel users when in Patagonia and they had no complaints (ever been in Patagonian wind?).

If you pitch cleverly you can off-set probably all disadvantages of a tunnel, they are quick to set-up and so spacious.

The geodesic is now my comfortable 1 man and his dog tent when I go off alone. Otherwise it's the tunnel.

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