I haven't measured my supers recently Shane, but I got worried one time when dozens of bees were squashed between the bottom of the frames and excluder, so added a bit more height. A bit of propolis doesn't worry me and sometimes I think the bees don't care as much for bee space as we do.
Mind you, my older bottom boxes have an extra 2 inches of height to fit in the first guilfoyle traps I got, and I end up occasionally hacking away at the mainly drone comb. That doesn't bother me either. I am just happy and grateful to have bees.
I'm not sure where my supplier gets the supers from, but we've ordered a few professionally made ones recently instead of having to try and fit everything together using 19mm pine which is all we can get here. I guess I can find out the brand and I guess also it will be queensland made.
Lone