I'm pretty sure while I was researching their kits all of them run about 1/2" higher than advertised. I just installed their 1.5" premium kit on my 2018 JL Rubicon and it was about 2" of lift - and very happy with it.
Standard stuff on long slow speed climbs on hot days from what I've seen (2018 JL Rubicon) I don't see temps that high under normal driving conditions though.