Feedback on Microsoft as services provider

Dear all

We are currently in the process of evaluating teams to replace Skype for business in our company.

So far we are, we have differents offers for transition but none of them speak about the possibility of having microsoft as provider and get rid of any other carrier.

Did any of you use that option? Was the migration/ the transfert of existing number quite smooth (https://docs.microsoft.com/en-us/MicrosoftTeams/phone-number-calling-plans/port-order-overview )? 

What are the pro/cons?

Our current setting is skype for business on premise with 250 user and less than 10 CAP phones