Air shocks??

I used to have those in the back of my Duster, to keep the rear fender from rubbing the 275/60 -15"s around a 7 1/4. Had less traction and stability than my current setup (8 1/4 rear G-60 tires).
What would I recommend? KYB´s or Gabriels (gas shocks) all around with stock or rearched springs (IMHO).