Probably Azureas or the uTorrent (with the weird symbol). I have quite a few friends who like Azureas and they prefer it over other cleints. I use uTorrent, but that's because I'm too lazy to go nab a download of Azureas.
i got uTorrent and was wondering if there was a better one because the downloads go about 20-30kb/s on average with the port forwarded and an excellent connection. When i download regular files from sites, it can go up to 150- 500kb/s.
use bitcomet it downloads at onehundred k/s on my dsl on most torrents. now remember the newer the torrent the faster it goes. some old torrents may have limited seeders.
i used to use bitcommet, but it gave me adware, so i started using utorrent. i like utorrent because it is a mix of bittorrent and bitcommet, - the web browser.