Well I’ll give you an idea of the good points and the bad points.
For me anyway
very quick to create
Fiber UV are excellent for transparency maps and gradient maps
Morph are so easy to make you can have a huge range of styles.
Rigging wise if you’re just doing short hair there’s no work in it, the transform template works excellent.
Close up with fiber mesh that has no transparency maps renders are terrible and blocky OK from a distance!
Mesh with transparency maps will render between 1h to 4h rendering at best quality but quick with default lights
Animal fur extremely hard to rig due to the weight mapping and you need a space between the leg or they pull on each other.
Daz file can be huge even when compressed
Very hard to get the poly count down and maintain coverage.
If you want to lean it Digital Tutors have some good tuts
I think only me and Mech4D are use it in production but more and more people are using it.
You can get unblocky/thin fibres without using transparency maps. Here is a new fibre I developed (based off my manfuzz fibre) that can be as thin as 1mm without becoming blocky when increased in size. This is on the freak who is huge, and it maintains its structure.
Click thumbnail to see full-size image