Why not use iTunes for pay per view/purchasing content? Their library seems very comprehensive.

I'm currently using Netflix and iTunes. I also have a prime account, but there's rarely anything I want to watch (the exception being Mr Robot).

I've bought a lot from iTunes, deals come around often enough. June and Decemeber. There are a fair number of films for 99p rental too.

Although their prices for the my favourite long tale films are seemingly always "moderate".

Network connectivity from the UK is occasionally an issue, Apple were planning to build a data centre in Ireland, but the locals were restive, I have a quality ISP.

iTunes is also dependent on who it makes deals with. I watched "Y Tu Mama Tambien" Netflix just before it was removed, and I can't get it anywhere else to watch it again.

BBC Store, and BFI have apps and a wider selection. The intention being you play it on your phone and ChromeCast or AirPlay it to your TV; I look for the BFI finnessing their app.

I don't buy anything Apple but, out of interest, is their pay per view offering more economical than amazon's?

Not usually as cheap, but the breadth of the catalog is remarkable. I'll go with Amazon for price reasons if both have what I want, but it's not rare that Amazon doesn't and iTunes does. (And Netflix almost never does. At this point I'm keeping it for season 2 of The Expanse and basically nothing else.)

Google Play Movies is another alternative for pay per view

Not sure, but for me it's more that the selection is better, I don't think you can get Westworld (series) on amazon yet for example.

iTunes doesn't have a workable interface unless you have an Apple TV.