Recently I started using 20lb braid as my main line and using a flourocarbon leader to my bait. I'm tieing the leader to the braid with a uniknot. I could take more time and tie a swivel in the line excluding the uniknot.
I've had some pretty strong fish caught on this setup (the uniknot)...even currently using 30lb mono as leader.
I'm wondering if this forum would agree the uniknot can be trusted and is a very good knot. You have no need for a swivel!