I just left the tethered to a carrier world..
After two weeks of use I am liking the
Google (LG) Nexus 5
I had totally forgotten about the Oneplus which I had found on a search a few months ago.... maybe it wasn't ready for release when I checked it out...
One thing the OS on the Oneplus is not pure Android, it is a custom Android OS built by a community....it is a very robust community with many talented people...
That said I don't mind that sort of challenge.... If you just want it to work....you probably have to stick to a carrier tethered phone..
I ported my # from Verizon.... the carrier who happens to have the tightest control of devices on their network, to Cricket which is Att (Aio and another) prepaids service...
It took about 20 minutes start to finish... and the Nexus 5 was fully ported in about 2 hours...