I have a Kindle and I like it very much. I've had it for a year and I've read a bunch of books on it. Not a single problem to report.
What I like most: The convenience. I can carry a huge amount of stuff with me. When I finish something, I can start reading something else right away. I can be in the middle of a bunch of different things at once (collections of short stories, etc...) and it holds your place & you can use bookmarks & make notes. Also, the Whispernet wireless is free and you can shop for new stuff whenever & wherever, get free samples, read reviews, etc...
What could be better: The back catalog. Almost everything new is available for kindle. And anything old enough to be public domain is available and either free or very cheap. But some slightly older books are not there when you look for them. Some publishers are not up with the 21st century and there are some chunks missing from the back catalog. But this is something common to all e-readers, not just kindle.