Adam - I installed Bosch +4 plugs in Winged1 about a year ago, and have been very pleased with them. They seem to stay clean, and the engine is running very smooth. Before the +4's, I ran regular Bosch platinum's, and they seemed to last >25,000 miles with no sign of deterioration. I now have the +4's in my Explorer, and my Dodge Intrepid, and have no complaints at all. I suspect that plugs are just like oil ... everybody has an opinion, and they are all different. As long as you use a good quality plug, and all the other components in your ignition system are top notch, I don't think you can go wrong. The medium heat range works well for me, and Winged1 has about 77,000 miles, so we are at about the same place in the life of our engines, all things being equal. At about $6 each, the +4's are a bit steep, but look at the "Split Fires". Those things were about the same price, and lasted a fraction of the miles before they were showing signs of wear. Toby Peterson VIN 2248 Winged1 --- In dmcnews@xxxx, "Adam" <acprice1@xxxx> wrote: > Can anyone who has used these plugs give me their opinion of them? >I am doing a tune-up soon and am thinking of using these plugs. >Also what heat rating do you suggest for an engine with 75,000 >miles on it, is it different for the platinum plugs?