Although Arnott offers a few different kits, most keep the air based auto leveling features in the rear but loose the electronically controlled dampening on both axles. The electrical dampening is highly effectively at reducing body roll and improving ride quality, and most of this behavior is a result of the speciality front shocks performance. In fact, if there is a problem w/ the SCM and the system disengages electronically dampening, it can feel like the front shocks are blown (it makes that big a difference).
Since there is no aftermarket substitute which maintains electronically dampening on the front axle, I strongly suggest going the Monroe 40044 route here and avoiding aftermarket. The rear axle is less sensitive to the loss of electrical dampening, so I think you are better off using an Arnott kit on the rear to save a few coins. Keep in mind the system consist of 5 sensors, 4 shocks and the SCM... if you decided to loose auto-ride you need to bypass the shocks w/ resistors and effectively your sensors now get ignored (but still must work to avoid service alarms).
I went through a similar experience w/ my Escalade. I originally replaced the rear shocks w/ the Arnott/Bilstein product and the front shocks with a strutmaster product (no more electrical dampening). I am now swapping out the strutmaster front kit w/ the Monroe 40044 shocks as the ride quality is still poor. I am fairly happy w/ the Bilstein/Arnott rear shock and will be keeping these. My vehicle is not lowered however...
Out of curiosity, how does your lowering kit handle the front and rear ride height sensors to keep them accurate when dropped?