I'm very sure all the ISA issues are clearly stated in the contract. Everything is very clear about the fact that you will pay a minimum of $17-18k, and a max of $30k as a percentage of your monthly income. It was very clear that missing a payment would incur the entire loan being owed immediately (presumably it would go to collections).
The "hidden $4000 finance charge" I don't really understand, given that it is apparently built into the loan. It's not like you get charged an extra $4000 on top of the $30k (assuming you pay that).
I'd still choose this route over 4 years plus college tuition for a CS degree.