Late to the party on this, even though I was asking about this when the topic was first created. For anyone who has not had a chance to see this, the first 3 series are available as part of Amazon Prime. I started watching this a few weeks ago and part of the way into episode 1 I was going to turn off and abandon, but I decided to continue with it.
In short, this is excellent, certainly one of my favourite series of recent years. It is particularly appealing to me as it is drama that kind of covers a fictional evolution of computing from the 80s, something that I have been around for. I have 3 episodes left in season 3 and I was already checking online to see if there is any more. Thankfully there is a season 4 coming this year, hopefully it won't take an age before Amazon gets it.