I have been using a Navionics Multi Card Reader for some time to supply cartography to Euronav Seapro 3000 & Raytech Navigator (v6.1) PC chartplotters.
Seapro requires a dongle upgrade to add the Navionics chart option, but this includes the card reader. Unlike Raytech the Navionics charts are loaded onto the hard drive by Seapro after which the card can be removed & used elsewhere, i.e
Raymarine C series chart plotter.
The chart licence remains valid during the period Seapro is running but times out a short time afterwards. After this you have to renew licence by inserting card into reader again. Nevertheless a useful feature.
Regards