Check the specs: CarCapsule has a stronger fan and thicker PVC. The CarJacket might be fine for a beater, but for a Porsche, I'd go CarCapsule. Mine has kept my 911 pristine for two winters now.

Honestly, that separate bag thing sounds like extra work. I just shove it all in and let it dry at home.

Been there, spent a whole Saturday chasing a rough idle because of that. A dribble looked like a spray in a bottle. You're totally right, it's just a quick and dirty check. It'll catch a totally dead one, but a weak pattern will still fool you. A proper tester is the only way to really know what's going on.