So the one time my wife gets behind the wheel, there's a flat on the front pass side. Totally flat, I would guess. She doesn't notice it, or the handling issues, and drives it 3/4 mile over gravel/rocks to where I'm located. Tire, wheel, all trashed. Of course, I have about 25k on the existing set of tires, so *what could have been* a $20 flat repair is now around $1,000, because the existing tires are worn past matching to a new one and may cause issues (according to several tire cos.). Assuming they're correct, would it make sense to buy a 5th tire (and buy an OEM wheel, because the OEM spare rim is battered beyond use), and rotate that spare into the mix? That way, if this happens again, I'll never have more than 5-6k wear difference between any of the tires?