Mike,
There are lots of options out there on subs. One you might check out are the Paradigm DSP series. I almost bought one, but did go with Axiom factory outlet in the end. The Paradigm DSP's sound great and are good value for the $$ IMHO.
I have the DSP3400 and am very happy with it esp for what I paid, good bang-4-the-$$.
ab030, it also depends on your location....a number of these subs are available at a decent $$ on the US side but are somewhat more costly to bring into Canada. On the other side of it, some of the Canadian subs like Paradigm, PSB, Energy ect are usually a good deal esp in Ontario.
2 subs vs 1 sub? why not start with one and see how you make out before spending extra on another one? there'e a lot of competition in the $400-700 range.
