Just pondering the question, I am personally not a fan of the conversion bumpers, I like the OEM engineered bumper, and will add a lip kit once my residence doesnt have a restrictive driveway.
But I am always open to "extreme" mods, I have been eyeballing the RTR wide body for many many months...
As my uncle told me, "If you and I were alike, one of us wouldn't be necessary." So go for it if that's what you want.
Side note...I actually like the Mach 1 front-end look better than the S650. To me, when I consider the lower bumper area, it is almost as if the Mach 1 front end design was intended to be a segway into the S650 design.