SP30 will be 2400 Watts for 6 TH/s!!!!
That's simply not true.
One month and a half and it will be true!
No it won't. They advertise 2500w for 6th/s plus or minus 10% (my guess is minus). They are extremely optimistic with their estimations assuming that they will have 0.43w/gh while overclocked. That is more than 40% less than the sp10 underclocked. A die shrink should only expect 30% improvement in efficiency.
Why would they not offer in stock sp30s as soon as they get them?
Because having a a couple hundred/thousand units in stock needs a lot of components ordered first and a lot of preparing.
This is the worst explanation I've heard. They have more than enough money to buy all the components for all 3 batches if they wanted to.
They chose to go with preorders because they know that they cannot sell their hardware for ~$1/gh in 3 months and by doing so they put tons of unnecessary additional risks on their customers.
I suggest you to get lots of SP30 miner. It has the best $/GH and the lowest W/GH. Check my sig (affiliate link + donations if you buy through it).
I'd also suggest never believing anyone trying to sell you something as an affiliate.