I have no experience with bittornado as I'm only familiar with bit comet. Which I'm very happy with being that it free and really simple to use why not give it a go http://www.bitcomet.com/

By the way I'm getting good DL/UL speed (compared to what I see in the peers section) and it 's very low cpu makes it good if your doing other things. For instance I've had up to 5 vid bt's going and I was still able to record my guitar.