My most recent $75 overnight via FedEx Express was not delivered on time (day late which mattered and why I spent so much) and they straight up lied about it. Only anecdata but sad to hear so many concurring stories.
FedEx lost the paperwork I overnighted to try and get my dog unstuck from customs during an international (California to EU) move and gave me the runaround for 3 days telling me "it'll be delivered tomorrow!"
UPS got it there in under 24h.
Weeks later I got a "your package was delivered!" email from FedEx. Fantastic stuff.
Needless to say I'm never proactively choosing them again.