Airbags added to your truck will help somewhat with the the ride and help smooth out the ride.
I added airbags to my trucks suspension and it did help with giving the truck a smoother ride and makes the truck more comfortable to ride in as well.
So adding airbags to your suspension will help some and it's worth it.
But what will really help with improving the smoothness of your vehicles ride is to not only add the airbags to your vehicles suspension but also add new and improved leaf springs.
Doing both those will help make your truck ride a lot smoother as I seen an even better improvement with my vehicles riding smooth after adding the new and improved leaf springs along with the airbags to the suspension.