yes, it works with your rsap app, except of some problems with the second sim-card, as you mentioned before.
Samsung S5 mini (dual sim) - SM-G800H
originally no rsap
rooted with russian rom G800HXXU1ANGD
Android 4.4.2 KitKat
VW Touareg I, build 2010 with Premium FSE & RNS510
After disconnection from car (SIM1), SIM2 is shown to be deactivated, but incoming phonecalls on SIM2 still work. To fully reactivate SIM2 it is necessary to reboot the S5 mini.
I didn´t test it completely, but the connection in car with sim1 seems to be stable and phonebook is working normally so far.
For me, it is okay.