Main issue is there is NO "power" able to be harvested in wind speeds BELOW 7 MPH, very little can be harvested at 10 MPH and to really get any meaning full harvest 15-20 MPH winds are needed.
You also need CONSTANT winds to really get any meaning full harvest.
I don't know about you, but I am heading for SAFER shelter if I have constant wind speeds of 15MPH or better!
You also need to have an open unobstructed area around the wind gen, that means no trees, buildings or other objects near the wind gen..
Wind speeds tend to be slower near the ground also so that requires a pretty sturdy tower along with some sort of base that is not going to tip over in high wind gusts..
Most of those small wind gen manufacturers tend to way overstate the output and often in small print the full output won't be achieved until you get to 20MPH + wind speeds..
In a nutshell, to expensive, very little output at windspeeds below 20 MPH and to much hassle..