I have also recently subscribed to SkyDemon.
From a planning point of view I love it. It makes the whole process so much easier and so much less hassle. That said, I am glad that I have been taught how to use a wizz wheel etc and do everything manually just in case.
From a navigation perspective I think it will be great. If it's any where near as good as my old 296 (I suspect it will be better) then I can't wait to make use of it. Again, I will always mark up my chart and have it to hand just in case.
I also think SkyDemon can be extended to make it even more useful. For example, it could be extended to calculate take off and landing distances. It already has the plane's details and the weather. All it needs are the runway details...
One question I have for any users out there though is do you carry your chart, or print off the chart from SkyDemon? Is printing the chart sufficient?