I have had a little experience with the early Freedom Cat ketches with the wrap around sails. Its hard to separate the performance of the rig from the performance of the boat. That said, I found the cat ketch rig with wishbone booms to really give up a lot of performance over similar size and hull shape boats. I found the rig especially poor upwind and dead down wind. The impact of the rig was less obvious on a reach. Having the weight of the mast at the very bow of the boat seemed to really hurt the motion of the boat in a chop. The wrap around sails creep around the mast and slat terribly in any breeze at all. I found it very hard to alter sail shape for the conditions so even if the sails could have been made to sail better in a wider range of breezes it was too complex a set up with controls actually hidden in the folds of the sail to get a proper sail shape for the breeze. I felt that the rig was at its worst in really light air and when things had piped up. I think that many of these problems went away as Freedom went to fractional rigged sloops with the sails in tracks and mounted on a conventional boom.
Personally, given the present state of spar and rig design, I have yet to see any real advantage to freestanding rigs and in boats under about 45 feet, to split rigs.