I was told that the polycom conference phones work on the SCM and you can use the conference button on them, unlike the OS7000 where you had to manually create the conference.

You will need a 3rd party sip phone license on the SCM in order to register the phone.

I never tried Polycom's on SCM, got them working on the OS7000 though, but different models (IP5000, IP6000, IP7000)