Didn't Ford fix the ecobooms? They had a open water jacket with slots between the cylinders which cause head gasket failures. I think they got rid of the slots. ?
Which Ecobusts are you talking about? The 4 bangers?
Circa 2018 forward Ford redesigned their V6 Ecobusts.
The 2.7 never really had issues. Still it went dual injection which is mandatory IMO. New turbos and different placement.
The 3.5 had major issues and got a complete redesign. New cam chain design. Dual Injection. New turbos and design. Ditched the preposterous plastic oil pan
All things considered, my opinion is the 3.5 is a better choice than any of the standard V8s from GM or the ancient 5.7 "Hemi".