Do you upgrade your cards and if so how hard is it?

Unless i see major lake depth changes then i normally leave it as it is.
After the purchase/subscription the first year is free to update. I think i saw them say if its after (1st year) then it was 50% off to renew it. So, i want to say its now 50 bucks to update your cards. Not bad....

here is a good walk through. Easier than it appears.

http://navionics.force.com/kb/articles/en_US/Knowledge_Article/How-To-Register-And-Update-Your-Chip/

Thanks for the info

What card are you running now? I would advise you to keep a close eye on the areas you fish and see if it is worthwhile for you do to so, right now Navionics is averaging around 20,000 updates per week across the US so there is a good possibility your lakes have some updating being done at least monthly. Check out the webapp for free, it is the latest and greatest that is updated through the database, just be sure to toggle the button in the bottom left corner to turn on the Sonar Chart layer.
https://webapp.navionics.com/#boating@6&key=omvvDnjx%7DP
There are lots of videos on the Navionics Youtube channel that show the update process from start to finish, with a good interenet source it really is only about a 10-15 min process and the website walks you through it step by step.
https://www.youtube.com/user/Navionics