Bulletproof sheet metal?!
We habitually take cars to the range just to demonstrate how easily they can be penetrated with service ammo. Even 5.56mm NATO gets thru in most places. 7.62mm NATO ("thirty caliber") doesn't even blink. Fancy JHPs, while great against animal tissue sometimes have trouble.
I noted on my frequent trips back and forth from Cleveland OH to Gettysburg when my daughter was in college that if I cut my cruising speed by 5mph I could get there faster and use less fuel. The required gas stop running 75 rather than 70 took more time than I gave up with the slower cruising speed. I doubt this is unique to this journey. Fuel mileage with the '17 seems a couple miles per gallon better than the '07. Different axle ratio probably helps.
-- Chuck