If you're in the US, you may want to avoid Samsungs after the S5 - they all have locked bootloaders, and you will not be able to move away from the Samsung ROM.

If you're in the US, you may want to avoid Samsungs after the S5 - they all have locked bootloaders, and you will not be able to move away from the Samsung ROM. Maybe you don't think that's important now, but chances are you'll be keeping the phone for a few years, and you don't know how your needs or wants will change by then. Also it's nice (and not very hard) to install AOSP/LineageOS to get a lighter, faster, smoother, bloat-free, but still feature-rich experience, without all the tracking and shady stuff that OEMs put in. I used to have an S5 with LineageOS + F-Droid (no Google apps); the phone was faster and the battery lasted longer than my new S9 (from which I have purged all the unnecessary apps I can including Google's stuff).