Josh, what the hell? You guys still have $500 of my money for an 'upgrade' that no longer exists, and yet here you are defending your company's actions in the most uncalled for manner.
Do your bit for customer service and refund.
Joshie, please tell, how does BFL Intend to resolve such issues.
A) Run off with the guys money.
B) Supply a free miner to attach the upgrade to.
C) Refund
Its a simple question, why don't you answer the guy..

They offered me a 'credit' onto my account for my next order. However, I pointed out that I do not wish to have a 'credit' or indeed order from them again, and they went silent.
No matter, I have my banks fraud team on the case.
I have it in writing that you have received my money, BFL. I also have it in writing that you were going to either process me a refund in BTC or bank transfer. Then, another of your 'colleagues' changed their mind.
Companies don't act the way BFL do. Fraudsters, however....
You may have a product, and you may have manufacturing difficulties, but that does not excuse you acting like a complete a hole.