For what it's worth, Germany also has Prime Video.
I also use it mainly because it's a requirement for their DVD/Blu-Ray rental service. However that got a massive price increase the last month - so I'm considering stopping to use both.
Regarding delivery the interesting thing is that before prime emerged nearly all orders here in Germany were delivered on the next day. Then prime came up and from there on orders without prime took 2 days and looked artificially delayed so that you would have a reason to pay for prime.
However Streaming and especially Amazons offering is no alternative for Blu-Ray rental in my opinion:
- The video quality for streaming is lacking.
- The amount of movies (not shows) that amazon is offering through VOD is quite low and most of it is old and uninteresting stuff. Outside of prime you can get newer videos also through VOD. But the prices are not really attractive when you can get a higher quality version on disc for a lower or equal price.