Click on the PBK link in my post - $295 is the price for the 500, you can choose to be notified by email when they get more in stock. As far as the 305 pricing goes, I have heard of them going for as low as $138 on ebay. You just need to google and look, or you can go to qbike periodically and check, but it doesn't include any of the UK sites.

500 is still relatively new, don't think they are going to replace it anytime soon - I would guess next year or year and a half out. As to how much longer they are going to sell the 305, it's anybody's guess, but you would be foolish to pay anywhere near retail for the 305, it's just not as nice as the 500.