I would recommend you s3. Buy s3 instead of buying s1.
A simple comparison:
S1 : 180 GH/s | Power Consumption : ~360 Watt from the wall
S3 : 478 GH/s±5% | Power Consumption : ~366 Watt from the wall
I know the price for S3 is a bit higher than S1 but it is worth buying. You can consume power with good hash rate.
Kindly,
MZ
Thanks for the heads up everyone I shall start investing in S3's right away. You guys are awesome