Deluge
I am a Deluge user, I run Debian Lenny.
I wanted to provide some feedback on deluge, I believe I have detected a logical error. When you download your torrents to removable media (usb drive, sd card) and start deluge when the media is not present it sets the torrent as having no download progress. It then cannot allocate space on the locations (probably because my user account doesn't have write permissions to the unmounted locations). This works as expected. It shows a nice error, etc. However, when you then insert the removable media and run Deluge, it resumes downloading but does not recheck the torrent files. This causes a corruption of the data, and by then it is too late for a forced recheck to recover any parts. The best workaround I have found is to pause all torrents before closing, then force recheck them each on every startup. I would suggest an option to add "force recheck on startup".
Thank you for your time.