Just looking for opinions.
Thanks.
If it's free power, and you have space to put 6 antminer S9's, i'd probably go in that direction.
Do be carefull tough, your electric wiring needs to be OK for this, and they'll produce a lot of heat and noice.
6 antminers:
6*$2100 = $12.600 (maybe you'll find some coupons to make it a bit cheaper, but you'll have to add shipping and custom fees)
6*1500W = 9Kw
6*14Th = 84Th
84Th makes you about $55 a day at current diff, block reward and BTC price
http://www.coinwarz.com/calculators/bitcoin-mining-calculator/?h=84000&p=2600.00&pc=0.0&pf=0.00&d=281800917193.19600000&r=12.50000000&er=738.25000000&hc=0.00
The roi will probably be between 7 and 12 months (depending on the diff increase and if you're lucky with the antminers, cause they can also break)
An other option would be to be cheap second hand ASIC's on this forum. Just make sure you calculate the ROI beforehand. A thirth option would be to invest in decent GPU's and mine altcoins.