I'm also with the crowd of pro-700 posters. I bought mine after comparing the the 505 and the 700 for about two hours at a Sony shop. I can only repeat the recommendations of the previous posters:
- Write down your requirements (For instance, I needed the ability to annotate.)
- Go to Borders or a Sony Style store and try them out for a longer period of time.
- Make a decision!
So far, I didn't have any problems with glare (tested a variety of lighting conditions inside and outside) or readability of the 700 screen.
In short, I'm happy with it.
Oliver