Agree with admranger, if you go carefully and methodically, you will be fine.

Air suspension does nothing for balancing the load across other axles, and maintaining sufficient axle weight on the front axle to not impact the steering.

What it does is lift up the rear so the vehicle is level. Makes it look correct. Keeps the headlights pointing in generally the right direction. But the vehicle is still carrying a heavy load some distance behind the rear axle, and that doesn't help vehicle handling. The good news is that the X5 handles very well to start with, so it tends to tolerate this load bias better than some other vehicles.

You need around 10 or 12 % tongue weight for proper trailer stability. More than that will just pull down the rear of the X5 more. Less will contribute to trailer sway. With a trailer and tongue load kept within the X5 specs, it will be fine.

__________________
2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue