For my uses and what I've learned of these 2 builds, I think this tarp is best suited to be built with like ends. I'm super happy with how they both came out but having a removable annex is a bit more time consuming and not needed for my system. I almost like the "rear" center zip as an entry/exit better than the "front" annex. I will put a stakeout point on both sides of the center zips on my next build. That way u can choose which side will be your opening and the othe half will be a large vestibule. If weather switches just move you stake to the other side of the zipper. Plenty of air flow with both ends half opened. Live2hunt, could you see any cons about building this with like ends?