I added the Center Points a couple of years ago and I can tell you they make a difference. How different from the non air systems I can't say because I never tried them. The Winslow already had shocks and while we didn't get a lot of movement in our rear kitchen the Center Points reduced the movement of stuff to almost nothing. Also, at the same time I got a Trailer Saver BD3 air hitch so to be fair I'm not sure how much impact it had but shouldn't have much on the trailer suspension. I will say that this is the smoothest riding rig we have ever owned, and we have had several.
One of the advantages is you can adjust the bags to compensate for the different weights on each side of the trailer. The fridge and pantry are on the road side of our Winslow and is obviously heavier than the curb side. I run about 45 psi the curb side bags and 60 on the road side. Hope this helps.
