When going to a long arm suspension, you need to figure out why and for what purpose you need it. LA provides greater range of articulation, droop and compression compared directly to a SA lift. Usually, the limitations of a SA are minimized with a LA, but other limitations are added with the LA and must be considered. Without modifying wheelbase and track along with a LA, all you really have done is add greater range in the suspension without the stability. SA lifts are limited to height due to the short arms. LA replaces this limitation but adds other limitations.
When you do decide to go LA, front vs rear suspension should be considered for the function, limitations, and capabilities. Front suspension has to consider the steering aspect of the axle, thus, if using a frame mounted box, there needs to be a track bar to counter against the push/pull from the box. If you are going full hydraulic front steering, there is no relation to the axle to the frame, thus a specific track bar is not necessary to an extent. its the same for the rear axle. When adding a LA in the rear, triangulating the upper and lower arms will eliminate the track bar. By eliminating the track bar in the rear, you minimize the torque steer of the rear axle. You also basically maximize the 'articulation' of the axle relative to the frame. Articulation is the movement of the axle about itself. Compression and droop is part of the the articulation formula but not exclusive.
