SS springs were designed for high power, drag racing applications. For them to work effectively, they are going to put your rear up in the air some. The whole priciple behind the super stock spring is to improve e.t. They have a 2" shorter front segment, which will require a longer front hanger, and they basically act like a traction bar under load. At launch, they will pivot the car up and force the axle/tires down, improving traction. This is why a properly set up mopar will lift up under accelleration. They are going to be a bias design, which means the right side will have more leafs than the left side. Don't mix them up side to side. This design is to counteract the torque steer produced by a high powered engine and allows the car to launch straight. With the torque a Hemi produces, you are going to need this.
Also, there are differences between B and E body SS springs. Get the wrong ones and they will mess up your shackle angles, if you can even get them installed.
While they can be driven on the street and aren't a huge detriment to turning corners, they aren't exactly designed for handling applications. This is because the arch was designed into them to lever the car up, and they do not accept high side loading very well. They also have a high spring rates to them, around 160# per inch, so you now will have a vehicle that has a higher rear spring rate than the front. Great for drag racing, not so great a combo for handling. For comparison, the stock mopar 4 leaf pack is around 110#, the oval track springs are 120#, the stock hemi XHD design are 140#. To get a good handling balance to offset a SS spring pack, you would need to run a 1.0 or 1.12 torsion bar with a 1" front sway bar.
Now, with that said, they will probably still perform better than some other GM or Ford leaf spring cars out there, they just aren't as effective at controlling lateral loads as a spring that sits flat when installed. Don't expect a SS equiped car to act like a circuit racer and you'll be fine.