my ride: X5 3.0sd Sports without self-leveling

I have been searched for a while to find out how much actual inch will be lowered even they claim 1.2" or 2" Front, 1.2" rear. most of ppl get more than the claim figure. But I was also told with Sport suspension, we could expect less amount inch compare to what they claim because stock sport suspension has already lower a little bit. for example, if they claim 1.2" drop, we might get only 0.9" dropped

Now I'm confused which scenario will be happened?

Any input will be much appriciated.

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X5 3.0sd Sports
Current Mod || 21' Double Spoke Black | Gloss Black Grill Kidney| Black out Front Mesh | Debadged | LUX H8 6500K | Interior LEDs | Number Plate LEDs |Dual oval tip Auspuff |AeroDynamic body kit |LCI tail light| CIC system Retrofit |DMS remap| Alcantara Steering Wheel|
Next Mod || Fog Light HID 8500K | H&R 2"/1.2"