Re: ANTMINER S7 is available at bitmaintech.com with 4.86TH/s, 0.25J/GH
Which batch is better I cant decide if more chips is better, or less chips but at a higher clock speed and also if batch 7 can be overclocked. 
lower clock speed if definitely better because you have a chance of overclocking if you want to risk it.
In that sense it is much more likely that B5 could be overclocked from 600 to up to 625 than B7 from 625 upwards.
people will know for sure re batch 5 by this Fri-St, re B4-today or tomorrow.