P650SE
AMOLED PWM is mostly a Samsung panel issue. Samsung loves disgusting levels of PWM. Samsung also go hard on the oversaturation because it makes colours pop so the average person is more likely to gravitate towards it. The s6 and s7 caused me immediate issues. Just unusable. the S4 caused me no issues however and was a very comfortable phone.
The first smart phone I ever bought was an OLED Nokia Lumia that gave me zero issues and I used for hours on end. OnePlus X used an older Samsung AMOLED panel and I used to use one of those all the time with no issue as well.
My LG OLED phones have been amazing regarding PWM (LG Flex 2 and V30) the flex produces zero eyestrain and has zero PWM - I use it to watch things for many hours on end. The V30 gives me eye strain (but not as bad as most phones) and has visible PWM on very low brightness but anything above say 20% brightness+ doesn't produce any visible PWM. The eyestrain on the V30 I believe comes from the OS as anything past Lollipop gives me eye strain.
tl;dr I think people on here are far too quick to throw away OLED as an option as I've used many OLED phones with no problem despite my inability to use new Nvida, Intel, AMD GPU's, new OS, new drivers, and 99% of LED backlit monitors and am fairly sensitive to PWM. I realise we all have slight differences in our triggers however.
Regardless avoid Samsung like the plague until they get their act together regarding PWM.
Edit; also re: burn in I've never once actually seen burn in happen in person across my many OLED phones and many other peoples OLED phones. It's more likely your phone will fail before this is a problem. I've seen slight dimming and more yellow whites on older panels used for years but it was a non issue.