Well, before getting carried away, it may be necessary to balance out quality with quantity. All the quality in the world won't help a bit if it dosn't have the power to keep up with the rest of the system. Stepping down in quality may be necessary to be able to afford some subs that are close, but can offer the necessary volume. It's about balancing what you want and what you can afford. Many high quality builders (if not all) do try to make it loud enough so that one will work just fine.