At the moment, I only own springers so, I'm on the light to mid weight pellets.
......... I may test the heavies when I have time.
In the 2 HW100s that I've had, I always used JSB Heavies for hunting.
........ it may be psychological but, quarry hit in the right place with those did seem to move less. Also, there seemed to be more of an audible crack when they hit the spot compared with something around 7/8 grains.
I think the shape of the pellet may be helping as well - being less waisted and having more mass, they tend to deform less so, they drill more of a wound channel - I've had some pretty decent pass throughs and, I've found pellets that have traveled a fair way in shot quarry.
......... it's the old debate about whether this or, dumping energy into prey is best.
I like the Heavies in a PCP - I found them to be accurate and reliable.
.......... as we all know, they don't kill any better than any other well placed pellet - they're just what I had confidence in.