I agree that WP devices, even the lowest-end 520 are pretty slick with the UI, and pretty solid to use.

The problem is that you simply cannot DO things with them due to the device being locked down!

If slick UI and stability are your main requirements, why not get a N9 or Jolla instead, where you have the possibility of making the device behave like you want, not like BillG likes it to behave?

Examples of some problems with WP; you cannot change look/feel/font/anything to be better readable, for example, you have no end of trouble getting any media in it, calendar alerts send always email to you, and it happens long past the event has occurred... (why do I want an email of the event for gossakes anyway?)