Is kicking very bad a good thing?
There are very expensive speakers from a lot of companies.
There isn't much difference when you spend $1000 for a sub.
Kicker is money well spent, The 13.5 JL W7 will sound better and hit harder than most 15's.
Just out of the subs that I have heard I think the Memphis MOFO is the badest,it just really blows your hair back.
Hope this helps