It's been a year since I asked this question! We settled on Google Drive, since Stanford (for now at least) has unlimited Drive access. Connection interruptions are handled well and we haven't had any issues with incomplete downloads since we started using the Drive desktop app.
What's everyone's favorite way to transfer data (for example, transferring 50-100 GB to or from a digitization vendor)? Our current methods are sFTP or physically mailing a hard drive and both make me want to quit my job