What on earth are you talking about. That makes no sense and has no effect on life of subs.

 

im talkingphyically. when people use the cargo area. people can let stuff rip or puncture the subs. when facing up they are less likely to be damaged.come on now think about it

 

The way you said it, it sounded like the subs would wear themselves out faster if they're not pointing up...

And they'll last just as long cargo wise, as long as you don't throw crap at them... Common sense