i am looking into buying one of these to put in the S, i figure its small and easy to install so it should be perfect for the S. but i have never used a tube shaped sub woofer before. do they sound good or overrated?

 

i thought about doing it when i first got the s2k but i went with the bass shakers. you mount them in the map pockets behind the seats and they shake like bass with the bumps, they're cheap and do it good. i already had an amp setup so i just hooked them up to the rear speaker slots...

 

 

where can i buy these? i actually never even heard of them.