On SMD i saw cracked windshield´s (alot), cracked roofes, broken trunk- and doorlocks, cracked trunkbottom´s, broken mirror´s. If you put on every 12 of your plan a Saz 2500 D you can get trouble with that. But with one 2500 for 4-6 sub´s you´ll be driving with a nice daily setup, without those problems.
Tell your family that it is a much bigger size of car-audio system is be needed to destroy a car.