For them and a lot of other companies on the internet I recommend using a Credit Card (Read that as NOT a Debit/Check Card!!). The Mastercard and VISA associations have provided consumers protections should the "buy experience" not be a good one (Dispute and chargeback of charges). These are "priceless" protections if you are considering any purchase that over any amount that you are willing to loose to an "educational experience".
Now if the question is" "Do they have a 'Cash Discount'?" Then, I think that the answer is no.