I'd rather have it outside rather than in the cab with me. I'm putting mine in the back with bracing around it plus a receiver hitch, plus the bumper. If it gets punctured after all that, at least it's 5-6 feet away.
My feelings are also swayed because I knew a family with a F*rd pickup back in the 70s. The fuel tank fire after a rollover claimed their little girl. I don't think the cab or the tank got punctured, but the filler neck either broke, or simply leaked gas when the pickup ended up on the left side.
One personal bad experience trumps all the engineering studies ever done.
