depends on if you can put up with it not being able to handoff correctly.. I have the 5s.. WiFi calling works.. just I've lost a few calls when I left home and forgot I was on a WiFi call.. LOL
They just.. stop.... then you get a call failure error.
Handoff appears possible with a compatible VoLTE device in LTE coverage area.
Source: http://arstechnica.com/information-...lling-its-network-cant-match-att-and-verizon/
Order update: Origin scan Saturday 1:43 AM ET Louisville, KY