What are the current recommendations for irrigation controllers? I would prefer something Z-Wave or Wifi if possible as the location for the controller is not that accessible but I think cost is going to be a factor here.

Possible options are
GreenIQ - limited to 6 zones, not expandable but it is Wifi
Solem 24V - Wifi, could be more than I wanted to spend but looks to do what I need
OpenSprinker - looks promising, any idea what the import costs would be? I can't find any supplier in the UK

Any other options I should be looking at?