I'm looking at getting a 2021 ED with air suspension.  I have heard a lot of issues with this on older ED's.  Has anyone had any major problems with the 2020 or later models?  I currently have a 2500 with CTD and rear air suspension.  No issues over 7 winters in the Rocky Mountain west.  When it's super cold -10 to -20 below 0 it doesn't like to lower when button activated, but other than that no issues.