I bought a first gen Porsche classic nav, it was defunct I spotted a blown capacitor in the power unit, repaired the unit
No map updates after 2011, and the updates were $200, no DAB, so I sold it on made $300 on it
That was a while ago, the new version is £1000 without the DAB antenna
But I quite like this cheaper version, found one on Amazon UK for £200 in my Xmas list now