But honestly, how often are setups in the same vehicle "identical". Unless you are setting all your gains with an o-scope (not many do), tweaking them with an RTA (not many people do), and have an extremely upgraded power supply that eliminates any and all voltage drop (again, not many people do), etc etc....then the setups are not going to be identical. And this doesn't take into account the on-board features that are by-passed in all the "blind testing".....which poorly designed internal crossover and non-bypassable features will affect sound quality. Hard reality is that chances are slim to none that two setups will be identical. Again, what works in a lab and in a showroom don't always work in reality.