I ordered the Cobb 3.5" catless mid pipe for my 2012 and should sound great. I am strongly considering the HKS Legamax( looks like I am ordering tomorrow). What are the advantages of the cat back ? Any issues with the HKS Legamax bolting up to the Cobb 3.5 " mid pipe ? I am looking for an aggressive sound with little drone OK, not major drone. How is this set up going to sound ? I am just wondering what is to be gained with the Legamax over the OEM cat back. Any imput ? BTW I am not looking to do any othe MODS due to my extended warranty, just want the GT-R to sound like a GT-R.