i just spam the checkout button and managed to check out
Strategy to buy:
Hit refresh over and over again until it says Add to Cart.
If it says error, go back and keep hitting refresh.
If you get to a page where there is a button that says Proceed, click Proceed over and over and over and over again and do not stop until the window comes up for payment. It will say Can't Process, it will say they are Overloaded, keep hitting Proceed even after it's greyed out until it works.
This is what I did, and was able to place my order for a 8GB at 3:27pm EST.