On my old 7.3 I was dumb enough to trust the minder, until I hit 60k and it still said it was ok. It had barely budged and I figured that had to be b.s. When I pulled that filter out it was black and completely full of crap. I don't know how the truck even ran with the filter so crudded. With the new filter in it fealt like somebody had taken a rock out from under my fuel pedal! I also got back 1.5mpg I had lost...
The loss of power over time to a dirty filter is so gradual you don't notice it until you get it back.
So NO, I'll never trust the filter minders again. I don't change the filter every 20k, because they cost so dang much, but I do change it every 30k whether it needs it or not. I don't even check the filter minder-- as I don't trust them either!