I'm another extremely satisfied skydemon user - so much so I quickly upgraded from the free web based to the full version.
I'd previously used navbox but that's now extremely dated, and development seems limited if not totally stalled. It did have a few nice feautures but not really worth buying it for those. Skydemon is being very actively developed and implements a lot of features based on user feedback. Things like airfield plates and info, and plog printing need a bit of improving but I'm sure it will come. But the situational awareness you get with notams and weather overlaid is what flight planning should be.
I tried rocketroute briefly, but didnt find it a very polished product overall - although google maps implementation and smartphone capabilities are very clever touches.
I'm mainly flying vfr in the UK, although skydemon has lots of Europe covered (no idea to what extent though)