Well when WoW first came out, boxing on the same PC wasn't too viable, only after it aged and PC spec's overcame the hurdle could you play 5 on the same PC at an affordable price. So it appears the trend is starting again with needing multiple PC's for each, give it time and you'll be in the same scenario a couple years down the road.

How are the casters in this game btw? I'm interested to try it out