abount refund:
apparently it's not at all what we hoped for.
As far  as I understood from the HF thread, all they
pay will be the USD price of the unit.
That is, we only get a fraction of the BTC we paid.

I wouldn't accept that.
(of course now every HF customer would gladly accept a refund
of BTC he paid. But that's not on offer, that's something we would have
to fight for.)

Orders are taken in BTC, in the unlikely event we get to refunds they will be given in BTC.