S8 and S9 are very similar, while the S9 has a better camera and that's about it.
I find that those two phones are very prone to a screenburn for some odd reason. Not sure why.
But both are amazing phones coming off from a S7 which is garbage compared to those.. onto a new level.
Even the moto X4 which I picked up from when they were on sale buy one get one, kicks the s7.