Hi I have a 2007 face-lift Sorento 2-5 auto. Had the previous model for 6 weeks before 'convincing' the dealer it was dodgey so they did me deal on a new one. had it for 3 yrs towing a twin axle & now a new sterling Ruby single axle. I found the suspension of the face-lift very bouncy as suggested in comparision. I fitted a MAD air suspension system, cost about £150 for the kit, took me 1/2 day to fit myself without any major dramas, didn't even need to take the wheels off.
Pumping it up with a simple 12v air compressor stiffiens the suspension as required, stops the yawing with the van in tow & dropping it downa bit when not towing provides a great ride solo.
Well worth the effort IMHO.