Any experience? Avid on iMac with AMD Radeon R9 M380

Hi.

I am currently considering to move my Media Composer installation from an old PC to iMac, but will it work?

I am setting up a few traps for myself by using a not-quite-qualified system with a one year old MC version. I own MC version 8.4.3 and have stopped support plans, since I mostly use it as a semi-professional/hobby system that makes no money.
Any comments to this:

Avid MC 8.4.3
iMac 27" Retina, 3,2 GHz, intel core i5, 8GB RAM, AMD Radeon R9 M380.

Will I run in to any conflicts with the operating system or the graphics card that is not mentioned in the list of qualified systems (there it says Radeon M290X)? 

Comments are very welcome. Thank you.
Chris.