For the best ANDROID experience, that would be Pixel hands down. Samsung's are not an android experience, they're a Samsung experience. They're the further thing from what Android was supposed to be. That much isnt opinion, theres literally nothing they haven't changed. Plus Theyre more locked down and you have no options with them. Maybe you become privacy or security aware, lots of options with a Pixel, zero with a Samsung.
Though not as bad as what it used to be (see touchwiz) and now there are several Samsung only things from GoodLock and gestures that pixels DON'T have that would severely limit my daily workflow so you have to find what is best for you and what you want.
Thats good, but given its an app that needs to be installed, is it really any different than than most most do with full featured launchers like Nova? If so, thats awesome for Galaxy peeps, but theres still me too many negatives, at least for me. But at least it shows Samsung is paying attention.
Third party apps like nova cannot go that deep into the system like good lock. You couldnt realy use nova and have great navigation animations for example.
I love my samsung devices as a poweruser because you can customize much more and they offer really useful tools which are missing when one uses vanilla android.
Also I would really miss the option to use smart tags which still arent available for pixel devices.