Regularly, miles are sold at 3.00 cents per mile.
The deal was good at 1.50 cents per mile.
However, credit cards are a better deal if one hasn't applied for a credit card yet. Assuming the spend requirements are met, by spending $499 on an Amex reserve card ($599 less $100 statement credit), you can earn one time 65,000 bonus miles. That's the equivalent of 0.77 cents per mile, which is a further discount of 48% from the promotion.