last i knew both v8s from fords suffered from plastic timing tensioners that would crack or warp. as they also used the same oil passage for the cam phaser and oiling for the front of the head that would all not be getting oiled. so they are in the same boat as where im at with the 4.0 and the same cost bracket for the repair.
As i understand it, the Ford tensioner maintains its pressure using oil pressure. If the oil is maintained well, the oil ports remain open and the tensioner operates smoothly. If the oil is not maintained properly, the ports can become constricted or the piston in the tensioner sticks causing the chain to slap and break the plastic tensioner. Also, the work to change the tensioner isn't nearly as bad as having to replace a cracked head on a 5.3, or replace the rear main seal. I've done both.
Bottom line is that all engines will have their issues at some point. It's all about what kind of work you are prepared to do. So far, my Tahoe has needed less work than my 4.6L Explorer, although the Explorer is 6 years younger.