I have a 2001 4.4sport and have lowered with H&R's. I have the rear air suspension. The kit came with springs for the front and shorter endlinks for the rear. The shorter links trick the rear suspenion and lowers the ride height.( No dealer dis thing was needed)
I believe its only needed with full air sus on all corners.
Nothing rubs even when I had 22"s on.
The ride is slightly bumpier but the handling is like a sports car.
I put about 5000kms on new tires this summer with this setup and recently swapped to winters.
I did not notice any abnormal tire wear on the summer tires.
And I also have 30mm H&R spacers on the rear.