Bingo! Don't bother listening to reviews on these boards. They vary so drastically at literally every restaurant. If the 50's Prime Time Cafe seems appealing, try it yourself and form an opinion. I had read dozens of scathing posts about Kouzzina. It is now one of my three favorite restaurants on property. The same can be said about 'Ohana, which has gone from the darling of the DIS to a dud in a matter of months.Do yourself a favor and don't take reviews too seriously. Each review is just one person's opinion. Pick places that appeal to you and form your own opinion.
Personally, I have been to 50's Prime Time twice and enjoyed it enough both times. I would return, especially with people who have never experienced the place. I think of this restaurant as an attraction more than a dining establishment. The food is just decent. The atmosphere is unique and classic Disney.