I did the same thing, I swapped out newer LJ springs front and rear. I gained 1 inch (measured at the front bumper) in the front and 1.25 inches in the rear (measured at the tub)
This happened for 2 reasons,
1) My springs are from 99 and they are tired from holding all the weight of my front bumper and winch, So they started to sag unlike my barely used 06 LJ springs I swapped in
2) The Spring rate is higher on the LJ springs because they are designed to hold up a larger Jeep with a bigger motor
I cant give a good answer on if it rides better, because I dont daily drive it, nor am I picky about stuff like that. Its a jeep with a homemade drive shaft of course it vibrates