I've got a customer who has 40 users on Office 365 E1, recently transitioned from BPOS. Right now they don't have an on-premises server at all; therefore, no AD - just workgroup with a QNAP NAS.

We're in the middle of a Cutover w/ SSO migration and the SSO portion was a complete breeze. Aside form hardware, it's not that bad. Since this environment is so small, having to add hardware is a ...