Wont use Vodafone for land line no matter what not today not tomorrow never as they still using their price structure base on pot services . SIP is ip generated service created by a computer server doesn't cost extra to have caller id voice mail etc etc as just tick box items within SIP server itself . Seems Vodafone wants to charge more for these service what a joke. O the stupid thing they expect is to use their junky modems to do this with. Cant plug it into your network with more one device as it crashes and it many firmware updates don't fix the issues see other geek zone posting to validate his. End of day Vodafone needs to wake up to fact that their are better 3rd party routers out there that do what there can do without requirement of many firmware updates . From consumer point a view this must use there modem is purely not acceptable in his day n age . Hopefully his might been seen by other Vodafone reps and something can be done about but I'm guessing it fall on death ear like so many other that have voice their views here in past .
I agree with you to a point in regards to pricing. But even though SIP is "ip generated" (as you put it) there are some very real costs associated with providing the servers/software that do it. DC/Server costs for one, but then the ongoing licensing and support contracts involved with the differing software implementations is serious stuff. And that is before you hire the team to manage the whole thing.
Vodafone forcing the use of their router is to be expected in a large scale VoIP deployment. It's just mental to do anything else.
The lovely thing about NZ broadband is there are PLENTY of other providers who don't care what router you use. You just need to decide what is important.. bundled landline/broadband/mobiles/tv at the lowest price (ie what 95% of the country look for), or pick a suitable broadband provider and a suitable SIP provider (even if the second best option (imo) for SIP has been swallowed by VF).