The triangulated 4-bar self-centers the rear axle, so it doesn't need a panhard bar. It also provides a true up-and-down movement of the rear axle, with none of the side-to-side movement you can get with a straight 4-bar. It's one of the most effective rear suspensions on the market. The only downside is that it makes the exhaust a little harder to route - but not much. Given the choice, I'd use the triangular every time. Pete and Jakes makes a good one. Make sure to use urethane bushings - not heim ends.