I'm guessing it's for those who cannot live without that extra, maxed out, 20-50 WHP on a BT kit, or who want/need that 'safety' factor within a maximal tune for WOT running.
It's just not worth it to me between the initial cost of the hardware, the cost and bother of constantly buying the stuff, switching tunes all of the time, and yes, having that stuff ANYWHERE near me inside the car, no matter HOW safely/precaution-wise it is done, and WHAT masonsturbos says.
But then again, no matter what I go to in the future as far as an aftermarket turbo setup goes, I DO NOT WANT any more than 300 PEAK WHP/LBS. FT. of torque going through the front wheels of this car, EVER, so I should not
need WMI.
I do regret not having E85 available closer than states away (it seems), since I would run E30/40 even now on the tiny factory snail and a tune IF I could get it.