SVS Subwoofers for music?

How good are the SVS subwoofers the cylinder series compared to the REL B3, Martin Logan Depth & Dynaudio sub 350 for music? The SVS seem to be a great value. My room is small 11x15x8. Thanks for any input.
Dynaudio Focus 140's
Plinius 9200
Naim CDP 5i-2
For Movies NAD receiver T762
All FMS cables.
You get what you pay for.SVS would be cost effcient for HT but muisc a multi driver sub will better it.
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SVS' SB12-Plus is a very musical sub. That is a welcome departure from SVS' previous, build a bigger box and driver to win dB "drag races" to impress the HT crowd, efforts. The quality of the upper bass was lacking in the older SVS subs, IMO.
OK, I bought the new SVS PC13 Ultra recently to match with Magnepan 3.6R's and for home theater. I knew that the SVS would be great for home theater, and although I really only wanted one sub, thought chances were high that I was going want a second "fast" sub for 2 channel. When the sub came, it was great at moving air with fantastic depth, but I couldn't really get it to match with the Maggies, so as I had resigned my self to the fact that I was going to have to buy a Rel, Velodyne, Vandersteen, or the like for to match the front end. As a last ditch effort though, I bought the Velodyne SMS-1 equalizer and that turned out to be a stroke of accidental genius. I was able to then quickly integrate the sub with the Maggies, and still get HUGE air movement for movies. I couldn't be happier. I really like the SVS product. They need to charge a bit more, and include an equalization system, or breakdown and pay Velodyne for theirs. Huge improvement.
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The SVS SB12-Plus looks very interesting. Has anyone had direct experience with this sub? Is it at all comparable to a REL B3 or others in the B3's price range? If so, it would be quite a value at less than half the price.
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I have a SB12-Plus in my office.

I found my friend's REL B3 in his home to be much more impressive.

The small size and price of the SB12-Plus was attractive.
Thanks for your responses. Bob, could you please post your impressions if you follow through with the purchase? Thanks,
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