There is no 15" sub in SV's current line. There is also no need for one. Their 12s are capable of ridiculous amounts of bass. Even their new $400 box with a 10" is insane for the price. Basically, SV's lowest sub is comparable to other subs in the $1500 range, and it goes up from there. They are accurate, powerful, deep...everything a sub should be, plus they are inexpensive.
Check out this discussion: [Link: hometheaterspot.com]
If you have any worries, ask Ron & Tom about it. They will recommend the best sub for you, even if it isn't their's. Although in that price range, it WILL be an SV. They have a good return policy, so at most you would be out the shipping cost if you didn't like it. The only thing I can see being an issue is the size. SV's are not small. Weigh the dimensions carefully. Oh, and the cylinders are actually 17" diameter, not 16.
I also have a 2039PC+. It is in a very large room and has no problems rattling, compressing and pounding both me and the room all by itself. I can feel it at 60db, and from there it just gets louder and more violent. Haven't bottomed it out yet.