I have opened my Airfix and find that, although the base/pedestal is shorter, the pieces are of a height with those produced by HBG. I’d feel comfortable using them on my board. My big concern is that the plastic is very soft, and some pieces so finely molded that you’re almost certainly looking at damage-in-storage, if not straight out of the box. They can also be a pain to cut cleanly from sprues, resulting in damaged to pieces during removal.
HaT pieces are in much harder plastic – so hard, it’s brittle. They are noticeably beefier than Airfix pieces in the same scale, but about as tall. I got a Serbian WW1 pack.
Waterloo 1815 miniatures in 1:72 scale are taller, also brittle, and beefier still, but are also acceptable. Sprues for special molds (e.g., machine gunners) are fiddly, creating risk of damage to pieces during clipping.