I have a 3 month prime membership , if you ask for prime video then I will describe it point wise -
Quality of video - video quality is good if you have better internet connection , it's totally depend on network.
Entertainment - you will not get each video in this site you will only get that , which is uploaded by Amazon and you will get some best movies.
Money - it's not very expensive to to get membership some other can also get benefits from using your id.
So , it is not so good to use but it is average.