[galaxy-user] Running development and live servers side-by-side

What is the best way to work with development and live versions of Galaxy concurrently and being able to have access to the same data (e.g. user histories)? Currently, I'm trying to run two instances of galaxy at the same time using the same MySQL database back-end and pointing to the same user files (via softlinks). Does this way madness lie? Although, it does seem to be working... I'm asking this because if we do go down the route of deploying Galaxy here, we'd like to be able to be able to test new tools without constantly having to restart the server and annoy the users. Cheers, Chris