Honestly, it's getting a bit late in this hardware cycle to purchase new mining hardware now.
I would wait until more efficient gear from Bitmain and/or Spondoolies is available.
Folks have been running with S3s, S4s, SP30s, and SP31s for a couple of months now, and in this game, it definitely does not pay to be late to the dance.
when invariably, waiting for next GEN will only assure a massive jump in network hashrate.
FC has released BE300 chip specs, so you can either start mining this week @40billion, or wait until ~March when diff could be 100billion?
it's swings and roundabouts.
BE300 thread here:
https://bitcointalk.org/index.php?topic=888260.msg9794133#msg9794133