I've avoided Samsung devices (including Galaxy Nexus/Nexus S) because the girlfriend has had the last 4 Samsung devices fail or become completely usable right at the end of the warranty (+/- 2mo) running completely stock. For those that became completely unusable it was usually pitiful battery life, the others became too slow to function on stock roms that I suspect they failed due to internal storage wear. Not even custom roms could save them.
I keep my devices a long time, and frequently repurpose them after they are no longer my primary device. Non-Samsung "Pixus" problems are overblown, except Nexus 6 AMOLED burn-in which is annoying but didn't present itself until it was used daily as a HUD.
Your choice in devices of the Nexus/Pixel series is very lucky, you avoided the defective models nearly entirely. I have no faith that I will be similarly lucky.
My friends seem to get a year or so before the SoC desolders from the motherboard, causing the device to bootloop, or the battery fails, or one of a million other things. Among us, there are a few dozen Pixels that are unusable due to their hardware defects.
Meanwhile, both of my old Galaxy S4's is going strong, and ditto for all but one of my LGs (one had its charge controller start smoking, LG repaired it).