I have a 530w with terrain that was installed in my plane 5 months ago, works well but I haven't come into any instances of actually having to use it...my A&P will be pulling it out at the end of the month and will be available. I am not sure how to pull up the screen that shows the system info, but it is the 14/28v model, with WAAS. Will be selling with the unit and rack. $8000 OBO. Will be yellow tagged as removed.