While gaming the avg temp is 65c. Sometimes dropping into the higher 50s, with the all core oc.You can probably live with the 84-86 degree spikes, but if it were my CPU I wouldn't want to see anything higher than 80°C consistently. Since you probably won't see those same temps most of the time you might be ok with it, but if you run ANYTHING that makes frequent use of AVX or AVX2 instructions, and there ARE plenty of games and applications that do, then you will want to keep a close eye on temps and you may end up wanting to drop your manual OC down to 4.2Ghz if you wish to see your piece of silicon last a nice long time.
While it's true that you are unlikely to cause any immediate damage at temps between 80-90°C, consistent temperatures in that range will almost certainly contribute to premature degradation through electromigration and VT shift over the course of months or years.
But my whole problem is that, this is only 5c cooler than the stock cooler, with the all core OC.
I just thought it was going to cool like, much better than it is. idk. As I keep finding more info, like this video at the 3 minute mark you can see while hes using Aida64, on a 4.4ghz OC while using a custom water loop, he hits 76c, so that makes my 84c with 4.3ghz on air cooling seem really good.
But idk what to believe because I keep seeing different results everywhere and my personal experience with this cooler vs the stock cooler doesnt seem to be that major.