Ok, for 2007 Grand Rock is looking at offering our QP muffler inserts for the stacks in our stack kits. These mufflers have done very well with the Class 7 and 8 trucks, with keeping noise levels down, helping with fuel milaged, and also some with performance. Now the question is, how many of you would use these inserts? They would definatly quite the exhaust, which many wifes would like, but when you get on them really sound throaty and mean. So we are looking for some feed back, what do you all think?