As long as you are comfortable building and deploying yourself I would always use the latest code (all of it not part of it). Our default branch in the source code repository is always intended to be stable code and if you do find a bug using the latest the turnaround to get a fix in the repository is very quick vs the official packaged release cycle.
I update this site and our demo site quite a few times in between releases myself whenever there is any interesting new code that I want to use. For example I updated this site yesterday so I could use the new FlexCartLink that I implemented recently in WebStore. This allows me to have a cart link configured in my layout.master file to show up at the top of every page. So this site is running the very latest code right now.
I recommend use TortoiseHG to get the latest code though, I do not trust the download links for the latest code that the codeplex site generates. I usually publish to a local folder and then do any cleanup or adjustment of files like Web.config before uploading to production.
Hope that helps,