Slow : I had a 4x10 we camped in for ten years. It was a bit tight for the two of us but we liked it. Many great trips. . Then I got a walk around of a 5x10. Holy buckets, so I cranked one out. We've nicknamed it Fat Bastard and love it. That extra 12" is huge, in both the cabin and the galley. On its first big trip, there was a six-wide Little Guy in the campground that we got a tour of. Frankly, I wasn't impressed. It was just too wide. At least for my tastes.
Ours is officially a 6X10 though closer to 11+ Nancy would NOT be comfortable in any thing smaller, but we do pay a wind resistance MPG penelty. EX I am behind the curve, what happened?
Slow, sorry about your situation, but, I am looking forward to seeing what you do on this new build! I should be pretty cool after all that you and learned and what you like and dislike about the other. Rod