The Banks system did wonders for 2 engines I have owned. It decreased the back pressure on the turbo, decreased the exhaust heat which increases engine and turbo life, and increased power.
I did note a small increase in mpg.
Overall, I 'd do it again, and again.
07 TM 40D;ISL 450 Cummins(upgraded). Very happy w/coach
Gnarly toad to scoot around.
Geocaching, hiking, fishing, National Parks, Civil War sites.