[QUOTE=Humminbird_Greg;951459]I’ve updated units with SD cards before that had screen snapshots, sonar recordings and Nav Data on them before along with update files for other model Humminbird units. Now it did not make a difference those times that I have done it but I don't know that it won't in all instances. It should make no difference but if you may want to be cautious and have only the software update file on it.[/QUOTE]

SD cards are not that expensive..sounds like it would be good insurance from potential problems...IMO