All my M3's are usually sitting at about 83.5 to 85c.  Right above them in the rack I have two S9's that are seeing highs around 59c.  Above that are two A741's and they show 33c/75c.  The cold side of the room is around 22c.  I haven't noticed any problems so far.

Also all my units have a 6" diameter duct going out though the wall into the hot side of my mining room. 

My fans are running around 4k.