I run what the door placards call out on air pressure - 50 front, 71 rear. Stock suspension, no lift/leveling, Bilstein 4600s on all four corners. Rides like a dream, easily the same (or even better) than my '01 1500. Goodyear Duratracs, E load rating. I've been under mine, as far as I can tell, stock torsion bars in front and leaf springs in the rear. This is also the family truckster, as we take most/all of our family vacations as road trips. If the truck road like shit, my wife wouldn't tolerate our 5,000-mile two-week+ excursions.
I just recently had that point driven home for me. A buddy was looking to buy a used 2015 2500HD Silverado. It was local to me, 300 miles away from him, so I offered to scout it out and test drive it. Yes, very stiff, harsh, bouncy ride. I was genuinely surprised how big of a difference it was compared to my Suburban.
Don't know what to say, either you guys got unlucky, or I got lucky. But I wouldn't expect a significant difference in ride quality between individual vehicles, or even model years, unless both you guys have '07s and they changed something (along with adding the 6-speed) for '08.
ETA: Or perhaps there is a possibility of different spring rates on trim levels? Mine's a 3LT, just about every option, almost like an Escalade. Maybe the fleet/LS levels get different bits?