If that kind of hack will not be overprice, people will buy them, but 300$...
I mean vBulletin is the absolute best damn board in the web, the amount of work to achieve that kind of result must be awesome but the price is not exaggerated, it's reasonable and people buy it.
But 300$ for a hack, vBulletin is even not that expensive.
Just my 2?
And for the people who to it 4 free, they all have my reconnaissance !