Much quicker than building your own theme from scratch. I also like the fact that you create the exact theme you want really quick.
It took me about a minute to figure out how to use it, but aside from that no complaints.
I used this to create a theme, and I was pretty amped about how quickly I was able to do it. As en engineer, it was so much faster to go this route that to custom code my own, which I can do, but I just prefer not to since this saves me about 10+ hours of design + coding.Dan Jones has used this product for one week.