Home Theater speakers on a massive budget

I would like to upgrade my current setup.

I am looking at getting an Onkyo 595 (here they are good, or at least better than the other mass manufactured junk out there, and relatively cheap on eBay and such).

I currently have a pair of Bose 9001, a pair od Bose 4001, a BIC CLR3 Center channel, and a couple of old bookshelf system rear speakers ;-) I know, high end.

I want to upgrade, but have little to zero cash to spend. I can sell all of this equipment, and I figure then I will have in the neighborhood of $500 to spend (although if I have to go to $600, i would).

That isn't much in the speaker world.

I was looking at the B&W 303 series...getting 4 DM303 for left/right/surround, the ASW300 for the Sub, and the LCR 3 for the center. (here: http://www.bwspeakers.com/products/gallery/range_gallery.cfm?range=419DBE04-EF4D-11D3-B01E0000E20E7DA6)

Here is the thing, though: I heard you should attempt to purchase all speakers in the general same style and make to get the maximum output. Also, I know subs are pricey, so if I can't have that right away, that wouldn't be a big deal.

DO you guys have any suggestions for some quality, low cost speakers? Have you heard these 303s? are they going to give me enough BANG for home theater?

Thanks a lot,

Nate