well, this won't help you narrowing things down
, but since you're on a budget you might want to look at the
ebookwise 1150. i just got one last month on ebay ; i think it cost me around 130$ including around 30$ shipping (to France... it would be cheaper for you), and while it does have some disadvantages (no e-ink screen, alas, and it's on the heavy side if you want to carry it with you a lot, in my opinion anyway) overall i think it's a brilliant device and quite possibly one of the best designs in ergonomic terms including the more recent ones (but i've never had the opportunity to try any others so i can't make a true comparison).
some excellent features particularly for students :
- price (check on ebay, they are around 100€ with a memory card included)
- dictionary look-up (mine came with the webster's dictionary, many others are available), one of my favorite features
- bookmarks
- search feature
- touch screen and stylus to add notes (you can add a blank page to write more, or just highlight / underline / write in the margins) which is useful for reseach
- very easy to read gutenberg project books on it (that's what i use mine for, mainly), as it can easily convert several different text formats and html.
some drawbacks :
- no wifi
- no e-ink screen
- the memory cards are limited in size (i can't remember how big), but i already have dozens of books on mine and it's only half full, and you can always store the extras on your computer
- battery is not user replaceable, however it does hold a charge for a loooong time (i've only recharged mine once since i got it and i've used it several hours every day).
you can get a lot of good info on this site, that's how i made up my mind. check the wiki for example if you want more specifics.