Is an AntMiner S7 batch 14 good?
The most obvious problem, it appears to me, is that they cost $1200. If you make $4 per day (assuming that's net profit after paying for electricity), it'll take about a year to pay for itself. That's assuming the mining difficulty stays the same for a year, which it almost certainly will not; in the last 12 months (March 2015 to March 2016), difficulty has more than tripled. 

Unless the value of Bitcoin rises substantially (faster than difficulty), I'd be skeptical of coming out ahead.