Wonderful review of the Sony 600. I love mine and find all the benefits you described. I got the adapter for charging and have no regrets about that. Waited a couple of months before getting that and I think that's the best thing I ever bought! Also I got a beautiful cover and light from M-Edge. I purchased the platform cover because I can stand the book up while reading at the table or at my desk. Especially handy if you are eating while reading.
Their light works beautifully. It's an investment for sure, but when you spend so much on the reader itself, the adapter, cover and light make it all worthwhile in ease of use and protection.