The problems I had with autolites were:
I first put them in... Not problem, especially on a warm day. Weather got colder and I relized that the car was never warming up... heater didn't work, ran lean and sputtered,when I gave it gas to get on the interstate, then when I let off the gas, it mis-fired and CEL flashed saying it was lean and a mis-fire. After a while of that, I changed the coil and wires with Borg and Warner, the problem persisted. I changed the plugs for another set of Autolites... Same problem, only this time, rattling valves and rods.I bought the Ford Racing wires and MSD ignition, still the problem. Went to auto parts store, told them about the problem, changed the brand to Motorcraft DBL plat and it worked like a brand new, well oiled machine. I now hate Autolites...
What about NGK? worth the money?