Actually for a given 'high" AoA like over 15 to 20 degrees deltas have less drag and more lift than conventional wings. Modern deltas have vortex generators as well, but so do modern conventional wings "ie. strakes" which are the dark magic part of aerodynamics, so you really can't place a particular plane in this generalization and expect any kind of valid conclusion.
You really need a complete set of charts to start making any conclusions.