Hsu Vt-12 vs. Sunfire Jr. vs. ACI Quake

I'm probably going to be adding a subwoofer to the Triangle Titus I ordered last week. I'm wanting to stay in the $400-$600 dollar range. I'm thinking of one of these: Hsu VT-12, Carver True Subwoofer Jr.(used), ACI Quake, or Energy exl-S8. I could get a pair of the Energys for about the same price as one of the others. My room I 11" x 17". This is a 100% music system no home theater. I'm not concerned with LFE only musical accuracy. I would like to hear from people that own these subs or people that have expierence mating the Titus with a sub. Thanks.
I can only speak about mating the Sunfire Jr. - it is very fast & natural as subs go, and will probably mate well. I have heard it enough to give it the nod over the HSU, which is not quite in its class,(although a good value) but I am not familiar enough with the Quake to rule it out. IMHO.
We cannot speak on the VT-12 -which we are not familiar with, but we do think that you will be truly impressed with the Hsu VTF-2 powered sub with your Triagle Titus minimonitors. The Energy e:XL-S8 is a good sub for $300, but even a pair of them wouldn't match the musical performance of the VTF-2. We have not heard the Jr., but we have auditioned the (Sunfire's flagship) True Signature, and find it to perform well, but find it to be overpriced for what you get -soundwise. We think you are paying for the compact size. We also have not heard the ACI Quake either, although it looks like a good performer, and we have heard some good things about ACI's subs as well. All in all, the Energy and (no doubt) the Jr. are good subs that should provide for a good resale value -if and when that time ever may come. However, we prefer music over marketing names, and would choose either the VTF-2 or consider the Quake as a music making match for your Titans. Like previously mentioned, we have not heard the Quake, but think that a company that doesn't market too much and has been around for 20+ years (and is still in business) must have something good to offer. As far as Hsu Research is concerned, we just like the way their subs sound -that's why we picked up their line. An industry leading minimal margin for dealers, but great product worth promoting. We hope this is of some help to you in your quest for a musical high performance subwoofer.