Can anyone provide a solid reason why to buy the S4??
I guess Bitmain won´t be selling the S3 or the S1 upgrades (I have some defective S1s) until they have sold their S4 mining farm...
The only competition now is the ASM Tube at $350 for 800 GH which is equivalent to $875 for 2TH but the electric costs are higher at 1.1 watts/GH
Asm tube will stop being profitable end of October
S4 will be unprofitable end of November
Pick your poison