My 2 cents......Great idea for a vehicle that's out of warranty......but, I'd first check with your dealer to see what liability this install will place upon your vehicle, you may wish to wait until 2018 for the install.
The red words are the ones that scare me along with the idea of running only on 91 octane and susceptibility to alcohol damage.....only a matter of time before the EPA makes 15% ethanol standard in gas regardless of the consequences and those with E85 engines will be sittting pretty.
So for the next 5 years and 100K down the road when you break down in Podunk 'cause something in your drivetrain craps out......instead of simply pushing the OnStar button for a tow to the nearest GM dealer for a free repair under warranty on your tranny, 4WD CV joints or transfer case, rear end, or top or bottom end engine work (because you know that GM will blame the install modification for the failure).....you contact simply contact Magnason and what?.....beg them to provide at a reasonable price repairs at the Podunk auto repair and livestock feed shop.......or wait a month for their evaluation that the problem resulted from a faulty install and you're SOL............. because I doubt GM will go anywhere near that modified vehicle for a free warranty repair (or whatever portion of reimbursement any third party may offer) for anything other than a broken door handle.