I've got a real high tolerance for rattles. I've never been stranded on the side of a road by anything that just rattled. I get stranded by things that clang, bang, vibrate like he77 and fall off. Install that cat back and crank the talk radio up to 11!
Seriously, I try not to let the small stuff bother me too much. My foreign cars rattle and squeak, too. Took them nearly 200k miles to do it but they do it...