I stick with those who condemn David Watanabe attitude toward his customers: he offer NO answer whatsoever. My personal experience.
On the other hand both Acquisition and Xtorrent are beautifully crafted. Functionally and visually. They're simply elegant and a breeze to use.
I paid for Acquisition a long time ago but now that Xtorrent is just out of beta, I'll switch to Transmission, that's been said has the same engine of Xtorrent.