ebay sometimes goes downto 230 for second hand,and demo models,shipping included.
I'm in the same position as you.
Yet I had no luck so far on ebay.
I see bids going in front of me for 222 (+ additional shipping), but when I bid they go up to 265
I've told my wife (who prefers me to wait), that I would,until the 700 comes out,and then decide.
Touchscreen is nice, and leds are ok, but not worth the extra $100 for me.
However some user said the screen refresh rate of the 700 is even faster than the 505.
Before I make my decision, I want to see if the 700's refresh rate is a lot faster or not (for anime pdf,and books), and I want to see about the battery life as well.
Should the display indeed flip pages faster than the 505, and despite it's touchscreen not use a lot more energy, I would definitely go for the 700!
So my main concern is the batterylife.
Apart from that, if you're familiar with ebay, you might want to buy a 505, have it 3 weeks earlier than a 700, and resell the 505 after a month or two with little loss,if you really find the 700 to have properties you miss on the 505.