But the Dash's difficulty is still around 37xx. It has been there for very long time. I am not sure if that miner is real or not.
I agree with you. Rumours of X11 ASICs have been around for years. But the total mining market on X11 is quite small, and I am not sure it will justify a development of proper ASICs.
When the Scrypt ASIC came out, litecoin coin was worth hundreds of millions. Now, the Dash and other X11 coins are worth less than $100 m.