Azureus is one of the best clients of .torrents file interchange.

With this utility you may efficiently administer all your downloads via BitTorrent with several improvements to increase its quality.

You may interchange all kind of files in an organized way thanks to Azureus.
It presents the option of grouping in only one window all downloads, and you may stop and restart each of them easily.

This piece of software functions in all operative systems, not only Mac but also Windows and Linux, so this is one of the most used tools.

It counts with an amazing stability that makes it stands out, as it has diverse and interesting functions.