Just as a non-interested party passing through as a result of seeing the insider purchases, my belief is that those purchases were little more than cheap publicity to get folks like yourself thinking the way you are "well, if they're buying, obviously there has to be a good reason".
From where I sit, again as a non-interested party, I think the stock is overpriced similar to others in this sector. Losses being posted (ok, it's cyclical), trading at over 4 times sales (can't really put a good spin on that), almost $500 million in debt (well, it is resource/capital intensive...but you've got to service that debt, and there's only $60 million in sales).
In my mind, that all points to overpriced. Not my cup of tea.