Dan. I know what you mean regarding sub pricing. I felt the same way when I started researching my speaker upgrades. After having purchased the SVS, I can tell you that I am very happy with that decision. You won't know just how much a sub contributes to the overall theater experience until you have something on the level of the SVS offerings. If I were in your shoes budget wise, I would make a temporary compromise on the surround or even front speakers, but not the sub. Have you looked at any of the SVS "B stock" items? They can save you some $$ and are not lacking in performance or workmanship.
John