I need to update my signature, sorry. My ez went bad and dodge charged me 360 bucks in Colo Springs to remove it and reprogram the truck. So I called edge and they sent me an attiutude for replacement cost, I think 600 bucks. It took 15 minutes to put it on, but another 20 minutes to drill and insert the temp gauge for the exhaust temp. Mpg went down and it caughs and sort of acts like a 56 chevy with glass packs when you let off the exhaust once in awhile on setting 2, the milage setting. I don't hear or read of many complaints about it. I get 19 to 20 mpg at 68 to 70 on I-80, nice and flat. But used to get over 20. There are too many things that can cause that drop, but the sputtering bothers me and I have to run it on setting 4 to avoid the problem. You may consider another system depending on your need. I only pull a 17 ft sylvan covered fishing boat, but still get about 16 mpg at 68. That's better that my brothers new Tundra, he gets 14 empty. Consider making a phone call to Edge before you make the purchase to see if there are any improvements in the last 24 months. If not, look into Mark Chappel's stuff. I met him once in Carson 5 years ago, and he understands diesels and people, I now wish I had gone with his technology. I still may... hope this helps...