UR has a lot of extra features, that are all listed on the website.
It has an external radio that is used by our JTAC players, integration with LotATC for our ATC players, it has a Transponder (IFF) feature, Voice Service for ATIS (yes, we can tune to a frequency and get the ATIS message via voice before taxi), it has a DataLink feature (we dont use it as many of our pilots fly in VR and afaik that is not compatible then since you need to export your mfd) and also an Emergency radio that detects when you bail out and then gives you radio functionality to talk to CSAR units.
Im pretty sure most of those functions are not of much use for most players/groups, but for us in the 132nd it is the radio program of choice.
Support by the developer is absolutely excellent and the one time cost of the license is absolutely worth it for us.