Interesting - I was killing Thargoid Scavs, so no bounty, not normal gameplay, but lots of 'em. 400 ARX in ~ 1 hr and I reckon it could go faster. The module buy/sell cycle is probably even faster though, but I hate the idea of it.
That makes sense anti-xeno fighting is a lot more specialized and cut-throat than just blasting pirates.
I've checked out casual BH'ing and I'm going back to just playing the game now, seems to be about a decal per hour maybe. I don't think I'll need to min-max it my usual playing style will fill the meter most weeks just doing BGS stuff and space-faffing.
I'm going to forget about it until I have enough ARX for some funky green lasers.