Basically they are a bank that prey's on people with bad credit. It is NOT a regular VISA/MasterCard, it is a card that can only be used at their site.
They have tons of fees, from an application fee to very high monthly fees(14+ a month). They do report to the credit agencies(supposdly) which is the ONLY good point.
You would be better off saving that money for a few months and getting a secured credit card from places like Orchard Bank. Here you put a deposit on the account for something like $300. They then give you a credit card with a credit line for the same amount. This is not a Debit card, it is an actual VISA or Mastercard. It reports to the credit agencies as a credit card, and if you maintain a good history this will help your rating over time. This includes making sure you never even come close to your limit, stay under 50% ideally it should be under 30%. Always pay your bill on time, even get it a week or more before to be sure it will post. Within a few months you should be able to apply for better cards without the security deposit requirement.