We recently took delivery of the new Yealink T55A (Teams Edition) Handset. The handset can ship with Teams or standard SIP but bear in mind if you buy with SIP there is a cost to move to Teams. The cost is the same SIP or Teams edition so make sure you get the correct software dependant on your requirements.
Adding this to your Microsoft 365 / Teams is easy, simply plug in, login with your 365 account and away you go. As you may know already Phone system add-on is required and this can be added on top of E1, E3 and E5.
Now you can use this phone as a teams handset and can call users internally, listen to voicemails and view your calendar. If you want to call PSTN/external numbers or receive calls then you need to also add-on the Call Plan license or work with a Direct Routing partner (much more cost efficient for 5 or more users)
Check out our video to see the phone in action, the teams admin page and direct routing.