I just bought one. We'll see how this goes. I at least got to use my $420 coupon, so it was only a bit over $2k all said and done. This all depends on how many they are going to sell. Considering they limited it to 1 per person, hopefully not a ton. If the 2,500 rumor is true, then that means around $100 per day with the current price. If that was bullshit and they sell 10 times that, then it's like $10 a day. Knowing my luck they'll sell a ton of them and the price of the coin will crash though. One positive though is that the coin isn't going to fork, which is going to be a risk with a lot of new models that get released in the coming months.
Edit: They just sold out, so at least that is promising.
I think you bring up the most important point. How many will Bitmain sell in batch 2, 3 & 4. With the A3 (batch 1 was $2375, batch 2&3 = $930, batch 4 = $520) They dropped the batch 2 price by more than half for a 40 day later delivery.
Think I am gonna wait for a batch 2 or 3 on this one. It is tempting, but I know that they will follow with more b3 miners. Many more and probably at half the price.