Here is the thing, changing spark plugs on my 4.0L SOHC is really not fun to begin with but how do you know that your getting the best plugs for the time spent. Champion, Autolites, E3, ...... and so many other brands. With platinum, double platinum, copper cores, .....and so many models. Which one is really the best. It seems to me that a spark is a spark. What are your thoughts.