Sub Confusion

Agree with those that suggest Rythmik offers better value and can be integrated better than REL.  I have nothing against REL subs, but they don't represent a good bang for your buck.  If you have the money and like audio jewelry, by all means get a REL, or better yet, 2 or 4.  Just realize you're paying more for looks, their huge marketing budget, and dealer markup than you are for superior technology. 

A pair of well set up Rythmik subs will make your system sound better than the one REL sub you would get for the same amount of money.  A well set up Rythmik (or many other brand) sub(s) will be "integrated" just as well as a REL sub.  A REL sub can be poorly set up and sound boomy or not well "integrated".  All this nonsense about the way it connects to your system making a huge difference is just that.  You either know how to set up your subs regardless of what brand they are or you don't.  Rythmik and many other subs provide you with more setup options than REL.

@jayctoy I have not heard the "Swarm" but it appears to be a great plug and play solution that is reasonably priced.  You can use just about any sub to get that "immersive" experience, as long as you have them set up in a distributed bass array.  In my case, my distributed bass array, or "swarm" if you like, consists of two Rythmik subs and two SVS subs.  The Swarm is a nice option that I would have given serious consideration to if I had found out about it before I bought the subs I have.