Hi I received my Mazda 6 175 2.2 L estate in January 2018 and the OS version installed is 59.00.504 I have not seen any reboot issues yet, but having had a 2013 version for three years of the same car I find the SAT NAV in the 2018 car to be a big step BACKWARDS compared to the TOMTOM version in the 2013 car the new one does not even know the speed limit for many of the roads where I live so get no speeding warning, plus Mazda tell me they either turn off the speed camera warning system or there is no speed camera data on the map in France (I have had both answers from Mazda). I also think the quality of the map is no were as good as the TOMTOM, plus I am told once the free updates end Mazda will charge £90.00 a year which is three times the price I was paying for the TOMTOM updates so I will most likely buy a TOMTOM unit and stand it on the dashboard, in fact I would recommend that to anyone thinking of buying the NAV version of this otherwise great car Alan