While DMS is pretty interesting tooling, I had mostly ignored it until recently. Functionally, the tool works pretty well. The problem is it requires a lot of privileges–you have to have someone who can create a service principal and you need to have the following ports open between your source machine and your managed instance:
While the scope of those firewall rules is limited, in a larger enterprise, explaining why you need port 445 open to anything is going to be challenging.
The technology is intriguing, though it does seem like there are still some kinks to work out.