Lots of us have the sony 505 and it is pretty good for grabbing newspapers and putting them on the device using calibre, as the last guy stated.
It doesn't have replacable battery, but I don't worry about it, since I get 3 weeks battery life with single charge and the unit can be left on for 2 to 3 weeks.
Maybe in a few years , I might buy a battery for it , which you can find on the net, but you do have to take it apart.
The other devices (itouch, dslite, psp, netbooks) only have 2 or 3 hours battery life , yeah, it helps to have replaceable battery, but, 2-3 weeks , not a problem for me.
Sony does lots of formats and super easy to convert stuff to format that works on device.
Most eink screens are the same, but the 505 is considered to be towards the top of the pile, but next year who knows.
Maybe go to borders and look at them in the store, I think the 300 is like the 505 but a little smaller.
Others can also point you in the right direction as to other ereaders they like.