I get my information and opinions from people who work in the industry and from
articals like this one in Home Power magazine, I'm not saying Popular Mechanics is not a fun magazine to read, but they don't tend to do their own research beyond interviewing the people selling the product.
When someone who has told me to my face that he would like to own a vertical axle wind generator and has been in the industry for longer then I've been alive, I tend to listen to them when they say start articals with "not a single vertical-axis turbine was reviewed in "How to Buy a Wind- Electric System," for very good reasons."
I have seen these kind of "generators" in person and have yet to see one that has a rated out put, partly because I have yet to hear of one that works, unless you define working as simply spinning, I can make the wheels on your car spin while on jack stands, it will go really fast too! but how fast will it go when you want to go some place? how much work, in real life will this turbine do? light your house... one room... with an LED... I made a wind generator when I was 15 that could do that, it cost me less then $20 to build.