you cannot travel to .4 or less without some kind of military firepower backup/escort.
with a fighter and 150mm rails, I can still target and hit you easily at 25km out. with bigger ships.. whoa baby stay far far away.
I think the point of .4 and less space is that its lucrative and assholes don't want you mining there because asteroids DO disappear when mined out. So if you want to mine out there, take an escort. if you want to go bust some heads.. load up some war focused ship instead of your big transport vehicle.