Hey thanks bud, appreciate the intelligent reply.Lots of stuff
I'm aware that I might have a one-off bad hub, but the seals are intact and I probably only get maybe 8 - 10 muddy rides a year. Nevertheless, the freehub has required stripping, cleaning and rebuilding several times to allow the pawls to properly engage. Buying replacement parts in Australia is more expensive than getting a new hub from overseas, so next time I get a wheel built I'd say I'll just ditch the thing and try something new.
For comparison, prices here in Aussie dollars...
Hope Pro II 150mm- $246
Hadley 150mm - $580
DT 440 - $249
King - Can't find a price on the 150mm but the 135mm ISO is $799