Transmission is just what I've needed in a BT client: fast, tight, elegant. Easy to use. The UI just makes sense, and it does all that I need it to do. I used Azureus for a long time before, and I don't find myself missing anything enough to launch it again. I guess that says something!

The developer keeps on improving Transmission, and is quite active on the support forum. Can't say enough good things about that.

There are also interesting test builds if you want to trade stability (I don't think I've ever had a crash, though YMMV) for the features that haven't yet made it into the release version. Or stick with the official releases and just happily enjoy the ride!

I'm very pleased with it.