About FusionPBX, i guess this is not a complete opensource solution, the dialplan area is hidden and you cannot change it according to your requirements (correct me if i am wrong)... overall functionality is good and support is alive.

and yes, bluebox seems to be dead now, howeverm very nice interface, completely opensource. i am having some issues in its customization and there seems to be no support alive!

also note that, the iso image has different bluebox interface and git version has different! and no one to help!