The real concern imho is NOT IF there will be an A4 miner, but if they will get trapped in the same loop as most ASIC makers of scrypt and sha-256 and on pre-orders
USUALLY 2-3 months or even later getting them out as working units. There's the rub. The 90 day warranty under such conditions from past asic makers endeavors
are also a concern in that the software/firmware to get these up and 'tweaked' to pools always takes 2-3 months as well...so about the time you get them up and
'sorta' behaving your 90 warranty is running out. In the KNC Titan's case they did not even have a working firmware till after 3 months as a example. (They tried
to setup a 90 warranty but forgot to fix the web sales page..thus could not do so after the fact..then again they abandoned support after like 9 months anyway)

So the above risks are 'pre-order' risks just to be clear.....the law of 'unintended consequences" or in 'Engineer speak" "Sure it will all work just dandy out of the box.
or part is backlog'd or the masking on the die is wrong and a 3 month re-do ..that kinda fun stuff.

But folk on here know this and took that bet imho.