Think about this.  Why would somebody go out of his/her way to host miners and have them mine so that you could make a PROFIT off of such an endeavor.  They would be dealing with the noise, heat, pollution, maintenance while you get the riches?  It is possible, but I can't really find examples of this in my life.

Having said that, I can't really find too many examples of where buying a miner earns you more than buying the coins.  BTC dropped to $560, it's even cheaper to buy now, makes more sense than 2 weeks ago to buy as opposed to mine unless you plan on solo mining.