RCD310: Downgrade from RNS315 (VW)

Hello,

I would like to replace the installed RNS315 with an RCD310 because the map updates are ridiculously expensive. I can currently sell the RNS315 easily, and then I'll have money left over for a portable navigation device.
"To continue using the FSE (Freisprecheinrichtung), I would like to install a compatible module. Which ones are suitable? I've at least found out that the D-version (premium FSE with Wi-Fi) doesn't work. Since I don't need rSAP, I don't need to run an antenna cable, right? The existing cable doesn't connect to the RNS (radio navigation system) anyway, but only to the phone holder, if I'm understanding correctly?"

Best regards,
SL

Hi.
I'm not sure which ones fit.
If you don't choose a car with the Rsap option (which also doesn't include Wi-Fi), you don't need to install an antenna cable. Do you have the larger MFA display in your car so you can also use the phone interface? The phone interface cannot be used through the RCD310.

http://www.carsystems.pl/volkswagen,c1.html
"There are plenty available there. If you have an MFA+ display, you can get one that doesn't require an MFL and then control it via the MFA display. Alternatively, you can also install an RCD510 and use it to control the FSE."