Actually nothing very exciting here
This just looks like a SIP based cloud PBX service charged on a per user basis. Lync, or any number of PBX suppliers like Aastra or Unify, will do this for you and a whole lot more.
I wish the MNOs would bring back the old dual number services that Orange used to have a few years ago. I get a iPhone from my work, who pay for calls and data, but I don't want to give up having a separate personal number so I still have an old Nokia for that. I know I could go dual SIM on an 'droid phone, but Im a fanbois who doesn't want to pay Apple or Samsung prices.