I don't think this is impossible to make--even with current technology.

The BFL jalapeno I bought has 2x65nm ASIC chips. Each chip produces about 3.5 gh. But if you just keep the same die design and shrink it to ~28 nm you can get nine times as many SHA256 engines in about 66% more space.  a 5.5Th unit would need about 185 of these chips.

Yes, you can "fake" the proof they have presented.

But I think there is a fine line between vapor-ware and a scam. In real life people announce products, and if there is enough interest (and faith that the presenters can produce) the products get made, if there isn't some people might get hurt.

But the environment has changed, people are raising millions from VCs and Angel investors all over the place for crypto-currency ventures.

Probably best to prepare for a lot of announcements and a lot of puffery in the announcements.