Well, rosetails are much like Halfmoons. Their tails can be heavy, so they may chew back their fins - which that is something you'd have to live with. Clean water would then be a must.
As for health, if you were to breed rosetail to rosetail we do not suggest it because there are problems in the genetics :)
I'd say go for it, IF you are willing to basically have a 98% chance of a tail biter.
Breed for the breed, not for the money; the words any REAL breeder would understand.
You must know nothing in order to know all, for all is nothing and nothing is for all.