I've got the outdoor version but a buddy has the indoor one. He loves it for keeping his Corvette clean over winter. The material is thick and the zipper hasn't given him any trouble. I'd say it's definitely worth it if you want a legit sealed environment instead of just a car cover.

You mentioned wondering which step makes the ring pop, and honestly I see it a bit different. That smoke ring is mostly just science, nitrites from the smoke reacting with the meat early on. Chasing a perfect ring can make you focus on the wrong thing, like how it looks over how it tastes. A good bark and tender meat matter way more than a pink line, in my view.