I upgraded our MY06 in June 2019 immediately after collecting it from Yorkshire. It had the original 06 DVD and the upgrade I got was a “2018” disc.
1. As you would expect, the maps are more up to date. Far from perfect but “2018” is the DVD pressing date; the map content can lag some way behind and is also subject to data providers such as local authorities being up to date, eg its got early stuff around here for the Olympic Park, but none of the recent 2015+ developments.
2. The firmware was useful to get a MY06 car to use the later format map data, but does not include a fix for the GPS week rollover. That would require GM to have asked Denso for one specific to Saab, so fat chance of that. Then again we should be OK now until 2038 when the next rollover happens.
I can’t really comment on other benefits of the firmware upgrade as my only use of the original firmware was on collecting the car, when it was obviously not 100% as my attempt to steer a course from the edge of the Yorkshire Dales to Nottingham (Saab) resulted in me being taken deeper into the dales

Pandemic permitting, I hope to get a chance to test that again this summer and see if there really is a homing pigeon inside it.
As expected, she rarely uses the inbuilt SatNav, it took years to get her to move from TomTom to
a phone App, so I expect another 2-3 years to make that transition.
As for me, I am a real man and don’t need a SatNav. But I do like the pictures.
