One can make very nice prints on RC paper. In fact, because of the faster developing times and easier handling of RC paper, you might get the feling from using them that it's easier to get a fine print on RC than on FB. However, try as hard as I might, I have never been able to get as fine a print on RC as on FB. There are certain tones that just don't want to come out of RC paper. I have done printing sessions where I have made the best print I can on my favorite AGFA fiber paper and then without moving the negative or changing anything, try to match the print on the RC equivalent of the same paper. I've never been able to get the RC to get on the same level as the FB in terms of print quality. And I've gone through over a hundred sheets of paper trying to do this.
So yeah, for a quick print where the ultimate quality isn't critical, RC gets me by once in a while, but the vast majority of the time it's only fiber that can get me what I want.