I'm using "stock" ones from Ames. No problems yet that I can see. Has anyone with headers noticed that when you shift into reverse the header hits the steering column (maybe not the right word...I'm no mechanic)? It doesn't look like it's "smacking" it hard or anything, but it looks like there's a bit of a dent in the header like it is hitting there. My car does make quite a loud noise when shifting into drive and reverse, but I think I've got that narrowed down to rearend issues. That will probably need to be a whole new topic...