According to the developers:
- Transmission doesn’t bundle toolbars, pop-up ads, flash ads, twitter tools, or anything else.
- It doesn’t hold some feaures back for a payware version.
- Its source code is available for anyone to review.
- They don’t track users, and their website and forums have no third-party ads or analytics
- Uses less CPU than any other GUI client, including some non-GUI clients
- Transmission also has the lowest memory footprint of any major BitTorrent client
Transmission has the features you want from a BitTorrent client: encryption, a web interface, peer exchange, magnet links, DHT, µTP, UPnP and NAT-PMP port forwarding, webseed support, watch directories, tracker editing, global and per-torrent speed limits, and more.