Medtronic (and Animas for that matter), have offices in several European countries (including the UK and Ireland). In the UK, pumps are funded by the NHS and would in general be replaced after 4 years (in some areas they try to drag it out a bit as a money saving exercise). There are NO upgrade programmes.
My Vibe will be 4 years old in November 2017. I have the option to get another Vibe, change to a Vibe Plus or switch to a Medtronic 640G. If the 670G is out by then, I might be able to take that as my new pump. I am self funding CGM (and there is no prospect of NHS funding in the near future). The predictive low glucose suspend of the 640G is attractive but the sensors are less reliable and because of their shorter effective life work out more expensive. Switching to the Vibe Plus would cost me the equivalent of about US$700 more per year because of the shorter transmitter life.
The idea of the 670G with a genuine hybrid closed loop system is a very attractive option (even if the annual costs would be greater than for the Vibe/G4 combo). However, given the likely delays in the release of the 670G I would probably have to continue with my current pump into its 5th year and hope that it doesn't break down. In three years of pumping with the Vibe, I am now on my 4th pump, so I am not overly confident about its reliability.