I'm a bit confused by the term "dwarf" angels? Are you talking about the commonly available Pterophyllum scalare type in the LFS? I've only heard of Dwarf angels in marine circles. There are the rarely seen Pterophyllum altum angels which do grow bigger, but aren't mentioned much.
The "normal" angels in the shops do occasionally have a go at plants but not to any degree in my experience. They did rip a few leaves of my Hygro. stricta and ate all of riccia, but everything else they've left alone.