I can't really answer your first question, but as to the second -- I would say probably not. Buying any miner from them right now is a risky investment, since:
1) it's hard to say when they will deliver; they initially promised shipments 7 months ago
2) many, many other people (in the tens of thousands) will get their orders before you, and this will increase the difficulty of the network. Basically, the more people mining, the harder it is for you to get rewarded for your contribution to a mining pool. See
here for a detailed explanation.
3) they apparently are willing to give people their money back most of the time even though they say their sales are final, but the wording leaves them room to just flatly deny refund requests.
4) the price of BTC may go up or down, making the investment worthwhile -- or worthless.
With that said, if you have the money to spare and want to participate, there's no harm.