I've had my entire car PPF coated since 2016 - Suntek Ultra is the one I went for. The latest generation of this film has better water repelling properties and is easier to apply for the installer. This is definitely the best decision/investment I ever made - already having paid for itself. That is because you would easily expect to pay £350-500 each time you get the car professionally machine polished/coated - which I've never had to.
Nearly 18 months on, the film is still glossy with minimal (if any) scratches. I am guilty of using just a QD/MF combo to do regular wipe downs myself, even taking her to Tesco Car Wash on the odd occasion😖. Safe to say the film has stood the test of time. Self healing works amazingly well, more so in warmer weather.
No downsides that I can highlight. Just be sure to apply PPF to a well corrected and clean surface and you'll be alright. Be VERY careful around exterior door seals as mine have started catching causing the PPF to lift on one side.
You can find more pictures on my Instagram (sam.7r).