I used to use both, but I stopped using DropBox. I didn't have any specific issues with it, per se, but Live Mesh works great, with 5 GB of space, and gives me a quick link to the rest of my 25 GB SkyDrive account. It does everything DropBox can do, with a little more. It has a one button option to sync my Favorites and my Office signature, templates, etc as well. I no longer drag flash drives back and forth from work and home.