Has any one used a duramilage brand chip? I am a new duramax owner, but I have had everthing else, cummins, powerstroke, gas, chiped them all with no problems. The thing is I have not hered of any one useing the duramilage to know if it good or not. It sounds great garranted 4 miles to gallon, lower egt, and pull with it in. Please let me know thanks.