(The above can be changed if the company advertised falsehoods such as BFL, but so far Terrahash has done nothing wrong (No matter what the "Kooks" will have you think))
Selling the Hardware once Terrahash ships is probably your best bet. People will pay a fairly good amount for HashPower in Hand.
If you are feeling a little brave and risky, you can mine with your hardware for 2-3 Weeks after receiving it and then Sell it for a decent price. As long as No HUGE players like KnC Ship during this timeframe you might come out ahead of just selling it when receiving.
Either way, there are still plenty of options. Hell if KnC misses their deadline this Unit could pay for itself easily. (I don't think KnC will miss that deadline)
That being said a 75% linear monthly difficulty increase isn't going to stay that way past maybe 3-4 months. Then it will level off unless you see some other big players selling $2/GH units. (Could happen!)
You have somewhat of a point, except that you fail to acknowledge that Terrahash bears the risk here.
Business is about risk and reward. The way that a normal business arrangement where this has happened works is this
You open up preorders for something you can't provide until you get parts from somewhere else.
Your supplier fails to provide those parts in a timely fashion, or at all
Your customers get upset or feel that they may never receive their merchandise and request refunds.
They have no business arrangement with your supplier - their business arrangement is with you. Their recourse for getting their money back is to get it back from you, and legally you are required to provide it.
Your recourse, since you have been harmed in this process, is against your supplier. In this case, since you've paid with a semi-untraceable currency that isn't official, your option is most likely limited to civil suit
Let's call this the way it is. Nobody wanting a refund (and using whatever option available to get it) is committing fraud. They are not harming Terrahash. They are protecting their assets.
Terrahash is being harmed, to be sure. It is Bitsyncom that has already harmed Terrahash, and I believe is continuing to harm Terrahash, not the customers.
Terrahash has already implied that they will not be able to refund everyone's money if the Avalon chips never show up. That, regardless of what anyone here wants to try to convince people, is NOT legal.
No business has the legal right to take people's money, never provide the merchandise, and then say but it's not my fault it's this guy over here so I don't have to give back everyone's money. I don't have, or see, any problem with someone deciding (in light of what's going on with Bitsyncom and TH admitting if it goes all the way bad they will not be able to refund everyone's money) that this is an unacceptable level of risk to them and they want out.
Now, you can argue but it's not them never providing the merchandise, they're just later than they thought! ok, great, but how long does one wait before you say ok the merchandise is never coming? 6 months? 1 year? 5 years? or do you suggest that people just say oh well, I guess if I die and I still haven't gotten my stuff, then I know and it won't matter?
That decision - where to draw the line - is subjective, and unique to each individual. Personally, I already believe that the avalon chips aren't ever going to materialize in enough volume to fill the orders. I firmly believe at this point that Bitsyncom, yifu, et al have scammed all of the businesses and the whole community, and are just making excuses to try to settle people down and buy some time - maybe to move the funds to someplace they can't be recovered and get away.
Does it suck for Terrahash? Yes. But the law (at least in the US) says that they are on the hook for refunds, regardless of their terms and conditions. Terms and conditions do not trump federal law and regulations.
Their recourse is to go after Bitsyncom for their losses and the damage to their business.