HI, new guy here and I have just purchased a 2015 RAM 1500 EcoDiesel with 56,000 mikes. The Approved Emissions Modification has not been done. I appear to have two options: have the AEM done and get factory warranty extended for 48,000 miles or 4 years; or skip it and get a GDE tune? Being new to the RAM family and diesels at large, your opinions are welcome. Thanks!