Hello Guys. I have a couple of those phones IP net . They are cheap sets, with not much quality on the making of the sets themselves.
Now, they work fine with my Quintum gateway/gatekeeper once I worked out some details.
They have a feature that is very nice. They will “masquerade” and I.P. address behind a NAT router. i have cable service with a Lynksys router doing nat and these phones are able to go trought it and register into the Quintum, using the I.P. address of the router,not the internal I.P. given by the DHCP server of the Lynksys.
I have seen a lot more expensive solutions that do not have this feature.
Not trying to sell anything, just a consumer.
Good luck!!!! By the way, those phones sell for about $80.00 american dollars a piece.