Hydraulics are the most prevalent in lowriders (some do air)
However, with minitrucking (what this is) air suspension is the most popular. While some do hydro I don't like it at all, but the setup's nowadays are actually pretty awesome for ride.
all of the trucks I have are on air ride suspension. Each has a different setup in the rear, but the fronts are all the same. Except with the 87 it's running tubular front upper and lower control arms.
2 of them are stock floor body dropped, the lime one is just bagged.
the 2 bodydropped trucks ride around and look like slightly lowered truck (unless you wanna showoff or parking lot pimp and then you can roll about 1/8" off the ground)
the lime green one that's just bagged it will lift up higher than stock if I want it, but it rolls around and basically stock height.