Vandersteen Sub woofers v Rythmik Subs


I really love the idea of the Vandersteen Subs where they are connected with the mains via extra speaker cable off right and left channels off the main amplifier, which is supposed to provide better bass transition from the mains while keeping the signature from the main amplifier. My question is with Vandersteen coming out with the SUB THREE and the price going significantly higher, I was wondering if there are other subs for less that you could integrate in the same way. (Most subs seem to rely on the line level input which is just a sub-woofer RCA going from the pre-amp to the amp on the sub). Can this same Vandersteen set-up be achieved with other subs?
I picked Rythmik since they are known (in the home theater community anyway) for being one of the best bang for the buck subs and the most "musical" of the bunch. (between Hsu, SVS, PSA).
And could I possibly achieve even greater sub-woofer nirvana since I could get an 18" for around $1500? Vandies only have 3 eight inchers.

I am a Vandersteen fanboy and I would like to support RV whenever I can, but don’t know much about my other sub-woofer options so looking for some feedback. Doesn’t even have to be related to Rythmik necessarily. If you know of other subs that can integrate the same way I want to know about it!

Thanks
bstatmeister
For me what's most important is to have the best experience possible in the sweet spot. How the bass does in other parts of the room is not as important as that precious, precious sweet spot. I think my game plan is to get 1 vandy sub to start with, then add a second once funds recover. (I will put the first one in the corner behind the left front main, then once I get a second, I will put it in the corner behind the right front main). Based off what I've heard I will not find anything as musical as the Vandersteen sub. Being musical is paramount. Although I enjoy home theater and would love to get the "dishes shaking off the shelves" effect, I really only care about how good I can get my 2-channel  analog system to sound.
Oh man
as a 2 bit $&@%#++++ hack of a bass player
“ just hammer A till I give ya the look”

cause the real rebel failed to show ( again ) for practice,

why do you guys always put us in the LEFT corner... ?
Lol. Does it make a difference? I think RV just said "a corner" for his recommended placement. Not sure he specified right or left if you only have one...
The Ampeg bass stack ( which was a sob to move ) was in the left corner.....

Get yourself a Leica Disto ($59 on Amazon ) and hone your setup
@bstatmeister - You are 100% on the same page as I was when I started to look for a sub.  I did exactly what you did, picking up one 2Wq, then several months later a second one, placing each in the front corner outside the mains.  And, when the material calls for it, these two subs can shake and pressurize the room quite well, IME.  One thing I would also plan on, is eventually upgrading to the M5-HP crossovers.  Not cheap, but worth every penny, IMHO.