Comparison of same and mixed-charge three-pion FSI correlations. $\Omega_0$ wave-function and generalized Riverside (GRS) method are shown. The calculation was performed in Therminator (0-5%). The bottom panel shows the difference between the two methods, $\Delta K_{3}=K_{3}(\Omega_{0})-K_{3}(\rm GRS)$, divided by $K_{3}(\Omega_{0})-1$.