The two dropper rig is the one I use most often. It is important to make it very strong in case a big shark or ray takes the hook. Most of the time I make them up with 95 lb (43 kg) mono. I tie my heavy rigs using 400 lb (180kg) Platypus monofilament. Sometimes I use wire. There is nothing more annoying than being busted off by a big fish.
On several occasions I have miraculously landed big sharks on light weight rigs that were intended for smaller species. For some strange reason these have survived not only the razor sharp teeth of big sevengillers but the sandpaper skin as well.