About the only situation where I (not anyone else, just I) might be able to use a descender is coming down off a spar that is ready to be flopped. But that would only be if I were coming down on the tag line, and we ALL know that isn't an acceptable practice.
I can descend using my hitch as fast as I like, don't see where a descender would help me. I like how this 8mm T-900 handles and it seems to hold up to the heat (friction) well.