I think I'll have to hold my opinion on this guy's exhaust mod until I see/hear the final version with the straight pipes that he says will be added. I admire him for having no fear about cutting off the resonators, though. It was kinda funny how his camera almost gets run over by 2 cars the second he drives away.
Anyway, it appears that we're starting to get some real world input on exhaust mods (better than waiting for the aftermarket if they'll be taking a long time). From what I can tell, it appears the valves may need to stay in the exhaust pipe somewhere to avoid either a drone, loss of back pressure (and torque) and to aid the MDS/ECO system for better mileage. This is based upon limited "testers" so far and any or all of those things may need further validation. I don't mind the concept of the valve as it saves me from the "other" loud noise I get from the passenger seat whenever I put an exhaust on that is too loud or drones. And, it may be that the aftermarket will come out with a cat back design for us that will include valves or require the stock valves to be cut off and reused in the new system (possibly clamped on). As I've said before, I would also love to see an aftermarket design that would include a new rear valance (either a new bumper cover or moding the existing cover) to allow a center exit exhaust. I'm sure it can be done but who will be the first?