Its a bit expensive; the free is ok yeah but its a crap address. If you buy a good package; you still need to be on their site - hence the crap address, and you still get dreadful hosting space. 10Meg will be quickly used up once you get the hang of it, and I'm sure they'll probably include the Invision Board Files in that space.
Eitherway - not much space, crap board, hardly worth $200
Considering PhpBB is Free and thats not noticably different other than that you get better Smilies and more Styles. You could pay $10, get a couple of times more space and bandwidth than on the $30 offer; PLUS get a fully customisable board free from PhpBB - and a domain name. Or, just $80 a year on that! vBulletin!