It's excellent construction. Did not work for the dog, but keeping and now the cat goes on walks with us in it.
My dog's girth fit's a ruffwear small in clothing, harnesses, etc. It's solidly 26.5/27". He is super lean but longer legs and topline (vizsla). I really wanted this to work for us so I could use this rather than the bike trailer.
I bought it knowing he was a little more than 40 lbs but his dimensions fit the small sized harnesses etc. because his body condition is mostly muscle which is more compact than pudge-kin 40lb dog from a volume perspective. To be clear, i knew this was a risk when we tried it and it's not ruffwear's issue at all, but for anyone else thinking the same thing who might try it and you're on the size edge: your dog probably won't fit.
I would say their statement "comfortable up to 40lbs" sort of implies to me that you could potentially, less-comfortably fit up to 42/43lbs and in our experience it should be more of a "hard stop at 40lb" notice. Meaning 40lb of properly conditioned, lean dog max will fit in this. My in-shape vizsla a couple pounds over 40lb I could not zip it over the hind quarters (like trying to get a boot over a super high-arch foot where there just isn't enough space) and as a dog with a longer topline (back), even extending the backplate was not tall enough.
It's super well made, and if you have a boykin spaniel, or a corgi, or similarly-constructed dogs I think you would be fine and totally love this. But most of…