That really has to depend on what features are important to you. Design, software, updates, SD card? Have you checked compatibility with the network(s) you expect to use it on? What is it you actually look for in a phone?
If you mean the S8, as opposed to the S8+, it is quite a bit smaller than your Note 4. That may be a good thing or a bad, thing, depending on your tastes, but I thought I'd point it out. There are still some people who think that the screen diagonal tells you the size of the phone, but since the screens are all different shapes at the moment it's a bit more complicated than that these days.