I wanted some advise on the 4" Silverline exhaust system for my '06 quad cab.  How does this exhaust compare to the other brands in price, quality, performance, etc?  Anyone have the "drone" sound that comes from some of these aftermarket exhaust systems?  I want to avoid that.  Also, should I expect seeing an increase in mpg after I add it to my S&B intake and Edge EZ mods?  

from my experience, if you are running a aftermarket intake with the factory exhaust, your actually loosing MPG, at least i did after i installed my k&n on my 98.5 24 valve before i upgraded to a MBRP exhaust, ive never dealt with silverline, but ive heard good things about them.  

I have the silverline and love it. I dont know about the drone, but its my first cummins with a muffler so it seems good to me. Its loud enough and agressive outside but waaaayyyyy quieter on the inside than my old straigt pipe. Its a good quality system, and i put it on with simple hand tools, actually one ratchet and two sockets i believe, minus the sawzall to get the stock exhaust out. I reccomend it to everyone. Ive got one, my fiancees little brother got one for his truck, and a buddy of mind is the one that reccomended it to us, he has 4 of them (1998 Dodge 2500, 1998 dodge 3500, 1999 dodge 3500, and a 2006 dodge 2500) and he heard about him thru his buddy Jeff Garmon, who has the Silverline Sponsored Dodge dragster that you might occasionally see in Diesel Power...they should pay me for this...hmmmm