We've definitely had our share of issues in this area, but we also take them seriously as you can see by the volume of patches that have gone in and continue to

We've definitely had our share of issues in this area, but we also take them seriously as you can see by the volume of patches that have gone in and continue to go in! With the very latest releases (1.4.7 and 1.5.1) I think we're in reasonable shape on volume mounting. And if you find things - particularly with the newer versions - please report them and we will work to fix them. We found and fixed another edge case recently, which was driven by an unusual real-world scenario (Xen not detaching volumes despite AWS believing them to be detached), and mitigated that. I'm sure we'll continue to find edge cases (and probably a few silly bugs as well), but we're also working on enhanced testing to really stress this area of the code so we can find them faster.