Yes, I have tfs heads and dougs and no problems. I have had dougs headers that fit like crap in the past though and more than one set but to be fair I have had a few headers fit like crap including the summit headers. Had those on my duster and went to cheap hooker headers and they fit much better, I then put on dougs and they fit the best, back to back to back so it was a direct comparison. When it comes to headers I think it depends on how bad the jig is and the dude using it that day. I would think if there was a problem with the tfs heads it would be common knowledge by now, I know of a few guys running them with no issues.