We are in throws of ordering a new 2017 Ram 2500 Cummins, prolly 75% of its use will be towing our 13,000# 32' 5W. Is the optional "Auto level rear suspension system" worth it? On our '98 2500 I added rear air bags, the rear suspension of our current 2500 was improved and I didn't add the bags. Now has the 2017 "5 link-link coil spring rear suspension" been improved to the point that Auto- Level system the is desirable or not?