When I finally decided to take the e-reader plunge, I came to MobileRead to do much of my research. The reviews, excitement, and help provided in the PocketBook thread led me to choose a PB360, and I couldn't be happier. I thought I'd share my experiences for those that follow.
When I started looking for an e-reader, I didn't think I'd want a 5" e-ink screen. It seemed too small. It's not. The compact size, the light weight, and the ability to hold the PB360 in one hand are all big, big plusses for me. I
always carry at least one book with me, but I'm usually reading two at the same time - one fiction and one nonfiction. I had to get a bigger purse just to be sure I could carry a hardcover book with me at all times. Now my load is much lighter and I don't have to decide if I want to go with fiction or nonfiction for the day when I leave the house.
I'm always reading on the go--waiting in lines, on public transportation, etc. I read when I eat. The PB360 is perfect for this as I only need one hand to operate it. The ability to change screen orientation is awesome. I remember the first day I was eating breakfast holding the PB360 in my left hand frustrated because I was unable to reach the buttons to turn the pages.

It took me a few too many seconds to realize I could flip the screen orientation.

The PB360 truly works great whether you are left-or right-handed.
I haven't used FBreader. I've been stuck using ADE because I borrow all my e-books from my library. As I understand it all the customization of the the reading experience can't be done in ADE. One small pet peeve. I'm rarely returned to the exact same spot I left off. Because page 156 can go on for a few pages on the reader, it always takes me to the beginning of pg 156. Not terrible. My spot is always close enough.
One big pet peeve.

The PB360 will not mount on my Powerbook G4 running Tiger. (I hear there is a fix being worked out?)
Finally, before I got my PB360 I was unsure about the experience of reading off of a screen and not holding a physical book in my hands. Fact is while I'm reading I don't notice that I'm reading from an e-reader versus a physical book. As for the experience of holding a physical book in my hands I do not miss it at all and actually prefer the PB360. Right now, one of the books I'm reading is a heavy hardcover and after a month of not toting a big book around it is a PITA.
Oops, I almost forgot. I love the hardshell cover and how it locks onto the back!
I highly recommend the PB360 for anyone looking for a great little e-reader. To the people at PocketBook