If you can find a 2018 or 2019 map update for under €100, it’s a worthwhile investment. Anything older than 2015 is not worth the effort—stick to your smartphone.
The latest stable firmware for CD500 is version (varies by region). Updating firmware is more dangerous than maps because a failed flash can brick the unit. opel astra j cd500 navi update
Official updates for the CD500 are rare now, as the hardware is legacy. Availability If you can find a 2018 or 2019