I love my Gintani tune. I cut my primary cats out, but left the res and secondary cats in. Its been about a year now and my car runs better than ever. As far as long term side effects I am unsure. Fingers crossed the tune does not cause issues, but as of now its 100% worth it. Nice thing is you can kind of control the amount of burble. It only burbles when you let off around 6k which I don't do often. If you let off the gas at 6k and let the trans slow you down it burbles like crazy which is not a typical daily driving technique. I usually push the clutch in and go to neutral when slowing down, because I figure new brakes are cheaper than a new tranny. That being said the burble is there when your really getting on it and not when normal driving. Perfect in my opinion.