I've got vals in my jack dempsey tank right now. I've had several different plant species in with my JDs and they don't mess with them much at all, but I have noticed that they will sometimes uproot them accidentally when they are hanging out around them by a clumsy tail swipe or close brush.
Doesn't pose a problem once the plants are anchored in well.
I have kept JDs in both regular aquascaped tanks and plant holding tanks and they don't do anything to hurt/destroy the plants apart from what I mentioned previously, so I don't know why they get a bad rap apart from perhaps their size.