Having cars with Xpel Ultimate and STEK I'll give you my feedback. Both are great films with high durability and optically clear. I'm lucky to have had FANTASTIC OCD installers with crazy great application skills both using bulk film - not pre-cut kits.
Xpel Ultimate
Had this on a 911 Turbo that saw lots of extreme MPH driving including road rallies. Held up VERY well and even took flying debris impacts like a champ. Scratches did self-heal in sunlight. Never had issues washing, waxing, edges lifting. No UV fade but sold the car after ~3 years of application. Still, a great product with 10-year warranty and peace of mind that it can handle the "heat".
STEK
Model 3. 10-year warranty like Xpel Ultimate and fantastic clarity and honestly nobody can tell it's even there. Again, bulk film install and the only edges seen are on the mirror caps and the "hips" of where the rocker film extended up the 1/4 panel. VERY hidden edge and that most likely due to the car being white. The Teslas get lots of mileage as they are daily driven and so far the STEK is holding up great. No issues washing, waxing, film lifting. Hydrophobic quality is nice and beads water very well. I'll have to report back after 3-5 years or longer and see how that is doing. I did get an impact on the hood and the film has a VERY TINY tear. Whatever hit it was enough to penetrate so no self-heal. (It's really minor though)
I would have gone Xpel Ultimate again with Tesla cars but no reputable local installer near me. Once I met my local guy and saw his work with STEK (Lambo, Porsche, RR, Aston Martin, etc...) and attention to deal it was a done deal. Warranty protection is important and if ever any issues arise he'll be there.
OP: Nealp97 I see you're in Florida. If you want my installers info - PM me.