Way back when, people used to say the demons in Azshara had a better drop rate of felcloth, but it seemed about the same to me. You’d get a string of luck and get several close together, other times, it seems like you’ve been there a long time before even 1 drops.
I’d think the felcloth gear would be outdated just like practically any old world gear, by the greens you get in outlands. Unless you meant you’re lvl 60 and 300 tailoring but don’t have BC expansion, in which case, they are some good gear pieces.