At the end of the day it's up to the shooter. If he/she wants to spend time experimenting with different size heads amongst other things, that's fine. As a C/F benchrest shooter, years back, I along with others constantly searched for anything that would give an edge, anything. Old habits die hard so nowadays, playing around with benched air rifles I'm still looking for ways to shrink my groups so, as I've already said in the previous post, I've found that head size does make a difference, slight, but a difference all the same, not only with the Steyr, but other match rifles as well.