I've been with iD since it's launch in 2015. I've changed tariff a couple of times as better value plans have become available. Coverage is fairly good - my reason for changing back then was that Vodafone just didn't work in locations I was spending lots of time at. Moving to iD was an immediate improvement. Everything can be managed from the app. I've only contacted customer service once a few years ago, I only had to speak to one person and once they managed to grasp what I was asking for it was sorted immediately. I don't know what there is not to love really.