One day I will do the Mountune exhaust assuming I do not change my mind another 5 times.........but until I do other things first ( Brake lines, RMM, shifter, FMIC & tubes) I did the "resonator delete" and am very happy with the sound....doubt it adds any performance and after a 400 mile road trip yesterday I can say zero drone. So if you are on a VERY tight budget then this is an option to get a little lower tone and slightly louder sound. Many aftermarket exhaust systems simply do away with the resonator and add a higher flow muffler. I do not believe there is any real advantage to spending money on a "high performance" exhaust system without addressing air flow from the air cleaner to the tailpipe. So until I save the $2K to do the complete job I will live with my "po' man's" Hi-Po exhaust system. I have also been known in younger years to drill mufflers to "increase air flow" (make louder!) I have since grown older and wiser and learned loud exhausts do not support a stealth mode of misbehaving as does an old guy in a plain white fiesta (ST). I am a true believer in a "Q" ship for fast road travel.