never tried them. honestly the motorcraft/autolite plugs are perfectly fine. i just switched out the stock platnium plugs at 68,000 in my panther and put in the autolite 764 coppers and the car starts up a little quicker, and feels like it has some more power than before. ive heard bad things about bosch plugs in anything but a german car. besides, i got 8 of the 764's for like $10 at Pep Boys.