Theres no power gains over the AMS DP. It sounds nice, but not worth the change from AMS

 

That isn't necessarily true. On a stock turbo setup probably not but on a big turbo there is definitely more power to be made on a external dump than on a widemouth style downpipe, the exhaust flow is cleaner with the dump. There is a reason all the T3/T4 kits have divorced downpipes.