Must admit the kindle I carry is the cheap Kindle.
Its light and fits in poackets in a cover. The battery still lasts ages even if you forget to turn the wireless off.
You can use the email browser on it.And I do occassionally if i quickly need to get something off a email but its not very good but works.
If I need to have web pages for directions etc I just print to pdf and send it to the kindle as a document.
The Kindle fire for me anyway goes away from what the kindle is all about. For me its something thats light and portable and I can read books on and I can purchase english books anywhere in the world. If I need to web stuff I use a computer.