I used Azureus for years and loved it but year after year they kept adding to it and it just became a bit bulky. To give you some idea, the download is nearly 3 times as big as most other clients.

The add-ons for Vuze are great though - try "autospeed" - it regulates your bandwidth so you're always getting the best download speeds possible for your torrents.

I use BitTorrent, uTorrent is also a popular choice.

Edit: Just read about a new torrent client that will allow you to access your downloads from anywhere as well as download from anywhere - http://torrentfreak.com/utorrent-spreads-its-wings-with-falcon-100131/