Though all three companies, Avalon, btcfpga, and bfl have all had past products in the fpga market so it is reasonable to assume they are not scams (I hope).
I threw some cash at "BTCFPGA" but ignored the other two, purely because BTCFPGA allowed the use of a credit card.
Any no show would be wire fraud, plus the CC company cover for non-delivery.
The other two have managed to convince me I'd rather not take the risk until they have at-least one device out in the public, basically because they are black hole financing, with ZERO chance to recover funds if something goes wrong.
um, I bought my BFL SC with Paypal...with my credit card.
I had also considered that, but
you paid an extra 5% and you will NOT be covered by the credit-card insurance.
The responsibility is then.... "you"-"paypal"-"BFL" as opposed to "You"-"Credit Card company"-"BFL", and I can tell you now that Paypal does not take kindly to credit card reversals against a paypal account.