I had this switched on a few years ago but ended up canning it: It would grab any crappy wifi signal out there (including in cafés) and switch over: cue for bad calls, lost calls etc. Only use was on the London Tube which has wifi in most deep train stations but no 4G.
Bop 'til you drop
MB Pro 13 | i5 | 16 Gigs of shiny DDR RAM | 1TB SSD - we have arrived...
iMac 27 i5 16Gig 1TB
iPad Air 64Gig
Time Capsule 1TB | 4TB connected HD
iPhone 6: "Too big, but bloody fast..." & a bunch of ill fitting ear buds
Canon 7D proper camera with nice L glass and Lightroom 6