My question is how good of quality are the replacements? Walker sells one pretty cheap but on some sites they say its aluminum, and others say it's steel. I don't want to have to do this again in like 3 years, so I want

something that will hold up in the Michigan winters with all of the wonderful salt.

I guess another option could be just replacing the whole cat-back. But I have to look more into that. I'm not sure if I'll like the way it sounds.