Well, there really isn't a "best" BT client. It all depends on what client works best for you. I use BitTornado and it hasn't given me any problems so I stick with it. Most people here also use Azureus (mainly for the batch torrents so they can either download just that one episode their missing or download like 5 at a time or something). Like I said, whatever works for you is the best BT client.