It's a great selection of fonts but the free font management app they talk about has fewer features than font book. Can't see the point it bothering to develop it.
In my download there were two fonts that conflicted with each other also. Seems that one of named incorrectly inside the file itself which conflicts with another font of the same name. I've contacted support multiple times and have been waiting for 2 weeks so far without any kind of response. So there's one less font than they claim.
Speaking of claims, the 6,200 fonts they talk about is a little misleading. There's about 850 styles and you get up to 6,200 actual oft files when you add up all the variations (bold, condensed, etc). Even so, at the current price of $50 it's great outstanding value.