Looking at a set of HM headers on sale.

What are these like campared to pacies? anyone tried em?

generally there more expensive than Pacey equivalents. there build quality and that seems good.
as for how they compare to others avaliable for the 8's I know jack s**t. just know a bit about HM Headers in general...

IMO you can't go wrong with either, quality, design and performance of both seem to be excellent. Pacemaker claim better flow due to their pipe over cone design but really, IMO you won't see any difference unless you have a very modified engine. Go for which ever you can get cheaper.