<font color='#000000'>First of all, keep in mind that a surround sound speaker system consists of 6 speakers--2 front, 1 center, 2 rear, 1 subwoofer. $350 averages out to less than $60 per speaker. You will find that fidelity is less than wonderful at that price, and so is output level. The output level is a real consideration, especially considering your vaulted ceiling, which increases the size of your room.
I would seriously consider doing it in stages, if money is a big issue. Get your front and center speakers first, then add the rear surrounds and sub later. If you absolutely must have a complete system immediately, of the choices you're considering I'd go for the Polks. They, at least, have a reputation for making decent inexpensive speakers. The others really don't. Neither does Onkyo, the previous post notwithstanding, although they do make some killer cheap electronics.</font>