Any experiences? I have them in my car from the previous owner. Not thrilled so far, but they were gapped kind of high (0.040+). Runs better after re-gapping just the first easy access 3 plugs. But should I ditch them altogether? Right now I'm sufferring through that stumbling/hesitation under hard accelleration, which may be plugs or possibly one tooth off the timing belt (last owner also did this by himself, and when I quizzed him on the procedure, didn't mention using any specialized tools).