We also have both and find Netflix a lot easier to find something to watch. If we know what we want to watch, it is easy to find, but browsing on Amazon is not very good.
One thing I have found with some shows on Amazon is they will offer one or two seasons for free and then want you to buy the other seasons. Netflix does not have current seasons and sometimes it takes a couple seasons before they'll add new seasons.
As for movies, Netflix rarely gets new releases. Amazon gets new releases, but rarely are they free. Usually they are available to rent for 24 hours. We only have Amazon because of Prime. The nice thing about Netflix is you can turn it off from month to month.
-Michael