My Delhezis have always gotten along with just about anybody, as long as they don't look like food.
However, my current Delhezi can be kind of rude when she is eating. For instance, if one of her dinner companions happens to have one of her pellets in their mouth, she will put their head in her mouth until they let it go. If Sgt. Maj. Blaine (bushynose pleco), happens to be sucking on one of her pellets, she will grab him by the fin and pull him off of it.
However, she has never done any damage and most of the other fish have learned to move out of the way.
In conclusion: Delhezis are great tankmates, but poor dinner companions.