I reviewed Amazon Prime Video last year and was unimpressed. I had another free month this year and here are some notes.

• Commercials are longer on iPad. If you subscribe to Prime you still get commercials unless you pay an extra monthly fee.
• Prime is $15 per month and no commercials is $3 per month so $18 per month which is the same as Netflix's standard plan of $18 per month... Actually you can get Prime Video alone (though how you get to it navigating Amazon web site, I couldn't figure out). It's $9 + $3 for no ads so $12 per month. Netflix ad-free is $8 per month.
• When you browse it shows programs from other streaming services which I think clutters the results. Would like those filtered out but there is no option.
• No independent volume control on Mac.
• Mac app always dims screen when paused and it shows video controls. And if there is X-Ray it also shows when paused. So if you want to examine a detail when paused it's hard to do. On iPad the overlay can be removed with a tap.
• Video quality is good but less good than Netflix,

A streaming service is not just the available content but the UI and usability. Paid Amazon Prime still feels second-tier compared to Netflix but I guess not as bad as when I initially reviewed it.