I'm collecting my new Stealth F16 this Sunday and it is rigged with a twin line system. I liked this set up as I will be able to deploy the tack from the wire prior to the windward mark, once round it will just be a case of pulling the kite up. To drop when I put tension on the spi downhaul the tack cleat will automatically be released (thats the theory). I'll take some photos in the near future.
P.S I'm copying a system used on a newish Tornado.