Playing with a Farnam rotator or plate rack, a few hundred rounds in 15-30 minutes, my G45 can't be reholstered AIWB. OWB, enough heat sinks through the holster that it is uncomfortable. One of my last outings I left the gun in a puddle for a few minutes to cool, shook it out, and kept going. Because Glock. I don't recall similar heat issues OWB with earlier gens, but I didn't think about them either. I also think I'm just shooting gen5s better, and therefore probably more.
I wouldn't think there'd be much if any difference, but who knows.