TestimonialsGreat tune. Its not night and day differance but you can tell its quicker. Had my wife drive it without telling her i tuned it. Asked her if she feels anything differant. She sa…I had been looking for quite some time for a product to give me a slight boost in performance with no luck. No one had yet to make serious performance upgrades for the CTS-Vsport. …The flash worked like a charm on my stock 2015 3.6l Colorado, took me maybe 10 minutes to complete. Love the way the truck runs now. I really wonder why they do not program the …The tune put some life into the truck.