well it depends on the lift, I had Revolvers for a bit, the problems I ran into to was my military Wrap spring would get caught on the Revolver head, and make my suspension stick. Also, the revolvers were about an inch shorter than my Boomerang shackles that I had on there.
As for your sagging, I would say the result could be the revolvers, they are different for front and rear and that may make a difference, however, being they use a z type swing out, they can allow the 4" leafs to sit flatter. A leaf lift gains its height by using longer, and more bowed springs, while still using the stock location, if the revolver allows the rear mount to swing out past its usual frame position it will allow the spring to flatten out thus loosing some of the lift.
Another thing, my military wraps would hit the frame in the rear with the revolvers, if your set up does, this can be bad. Alot of the reading I did mentioned that it can actually damage the springs to allow them to hit, and thus causing springs to flatten, soften, or even crack being they are hitting a rigid mounting point.
Now if you took the revolvers out, and now your front has sagged, double check your leaf count, BDS for example offers 2 different types, one is a 6 leaf for the front, and then the standard it the 5 leaf for the rear. But they also ask you if you have a hard top and then they will send you 2 sets of fronts, making it ride a bit harder but hold more weight. A lot of people think that the larger pack goes in the rear, but it actually goes in the front...
