I'm finally upgrading my Kindle from the Kindle Keyboard to the Paperwhite. That said, I'm still going to hold on to my Keyboard and use it as my backup backup reader

It's too nice of a system to part with completely.
What I want to know is what should I know about the PPW vs. the KKB? I use extensive collections and I just got them all cleaned up and organized in Calibre via the plugin. I've been reading and it seems like I can't use the collections plugin with the PPW without a work around... I'm just not sure where to start with that...
Also, most of my books will be side loaded. Since the PPW has only 2GB of memory I won't keep as many books on it and will leave most of the books purchased via Amazon in the cloud until needed. Is there anything I'll need to do differently with the PPW vs. the KKB?
Also, is there a way to get my side loaded books to sync read position between both of my Kindles? If so, how would I do that? (any helpful links appreciated)
I'm so excited to get the PPW. I bought one for my daughter earlier this month and I fell in love with its size and the screen. I can't wait for mine to get here tomorrow.