The top will be fine, just make sure it is complete as mentioned above.
The only difference between the Sahara and Rubicon suspensions is shocks with different valving, painted red. Otherwise, they are the same
The springs may be different spring rates depending on the options the vehicle came with, but you'll have to check the part numbers on both vehicles. The important numbers are the last two. There's no real advantage to swapping the springs unless you get at least a 2-3 number difference in the part numbers. The higher the number, the stiffer the spring. For example, switching from a 16 to a 19 for the front would provide a slightly stiffer spring and maybe a little more height, .5 - 1 inch. Switching from a 59 to a 60 rear spring wouldn't be worth the hassle.
You'd be much better off spending the money on aftermarket suspension parts.