Guess everyone's definition of serious is different. K-subs suck. You can get B'stock KW-181's for the same price and they pass everyone's kick ass for the $$$ test. DJ, Karokee or small live band gig the KW's are versatile and powerful. To get better you have to spend three times as much.
Great point!
Let me add, I like the KSub (and others) because the speakers are tucked away.
I don't load and unload my gear, so the better the protection from the factory on damage the better.
I know this seems silly, but it is what it is.