There are a few different types of drywall corners on the market these days, some of which I know from experience are stronger than the old all-metal types. These old-style corners work okay, but they are prone to denting and cracking. Paint chips off them fairly easily, too, because they come to a relatively sharp point.
A company called Trim Tex (800-590-5799). manufactures my current favourite corner bead. It includes a large-diameter curve made entirely of plastic. You fasten it to drywalled corners with spray-on contact cement. Besides being surprisingly tough, the large curved surface resists paint chips quite well.