I originally had the RC 2.5" lift kit installed. Non-SAS. There was some lift. It didn't look bad.
I upgraded to the ProComp coil over and did not re-use the tophat spacers. When I first installed the ProComp kit, I thought... well, since I originally had a 2.5" lift kit, I'll put the pre-load collar about in the middle and see what I get. I wanted to end up about the same.
Once I brought it down off the jacks and went around the block to get everything settled, I was up around 4" of lift.. maybe more. I ended up dialing them all the way down to minimum pre-load. At the minimum pre-load setting on the ProComps I was still about 3/4" over the RC lift kit.
The ProComps did settle about 1/2" over some time, a couple hundred miles or so.