The doppelganger puts a hand on his chest, gasping theatrically. He definitely has way more confidence than the real deal has. He seems to be practically brimming with it. They're as different as night and day.

"Wow, that's rude? What's to say that I'm not the bonafide Bruno? Real presumptuous of you to think that I'm not him. Me."

Except, y'know, the presumption is dead on the money. Except for that.