The Szikai configuration likes an addition base to emitter resistor with the larger transistor.
Another point to look for it that the Szikai configuration is more prone to oscillation, especially if the driving side is higher impedance.
The distortion in the class AB power stage depends on the standing current - both types tend to prefer a slightly different current. Better thermal stability leads to a more stable standing current and could this way cause less distortion. The simulation tends to no include that thermal effect.