Just another point, I have not changed my plugs (yet). I have been running the LMS tune (Stage 4+) for almost 2 years without any problems. I plan on changing the plugs at some point this summer, but I have not experienced any problems. However, I would caution you to be sure to change the PTU grease at about 25-30K, most of us have discovered that it is not lasting much longer and should be changed just to be sure you don't experience problems.