Well, a few things come to mind after reviewing the info on the website ...

1 - Turbos, by design, require exhaust flow to make more horsepower. Exhaust flow is generated by increasing engine speed. High engine speed is not what you need for rock crawling, etc.
2 - While that engine speed is ramping up, the horsepower develops. The more speed, the more horsepower ... as you would expect. Problem: during that time of low speed to high speed the horsepower is limited as boost has not yet been created by the turbo. This is called "turbo lag". So if you need HP now, you won't get it now.
3 - Do you really want all that additional turbo heat under your hood?
4 - Ever see the torque surge on a turbo engine?
4 - Did you see those prices? YOW!! I can replace gaso for gaso and have enough left over to pay for a LOT of fuel.
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