I've never used it for a long period, but I have tried it on other people's bows and here are my impressions (informed by what I have heard as well)
- slightly coarser than white hair, but less coarse than black hair (much like silver hair)
- a slight springiness or elasticity in the hair that is not present in black/white hair)
I liked it, but it's harder to get in general ( I've known people who send their bows to Texas from Toronto to get a rehair, which seems crazy to me), so I stick with black hair.
It's definitely worth a try, especially if a teacher has recommended it to you and you've got a place to get it.