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.
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.