IDC has evaluated Box, Citrix, Dropbox, Egnyte, Google, Intralinks, and Microsoft. One can observe that, each EFSS service was subjected to a series of tests that compared performance and reliability across three file sizes: small (less than 500K), medium (20 MB) and large (greater than 4GB) to emulate different use cases.
Their results show that sync performance is dramatically different across EFSS services because of differences in architectures and the choices vendors make in implementing sync capabilities.
Among the seven vendors, Dropbox and Egnyte ranked the highest in aggregate test results. All of the vendors passed their reliability tests.