I use the AHPC "dunny ring".
It goes up when I pull it up, It comes down when I pull it down. Haven't used the triangle so I don't know if its harder or not. Pole twist not a problem. More expensive than the triangle but very convenient, and they also a supply a pole to suit the ring (you cut it to size) and a chute made for the Mozzie
It's basically a viper pole and ring with a mozzie length chute. If you've got the bucks, it's easy to set up, and very convenient to add/remove from the boat. If you're on a budget, lot's of people use the triangle so it must be good. Plus it's always good business to do business with the President