My two pennies worth...
I too tried the skydemon light package and was mightely impressed.
So I purchased a 6" chinese cheapo SATNAV which arrived promptly 10 days later. This is the unit I purchased:
G602Y 6.0" HD GPS Navigation 128M WIN CE6.0 8GB NEW MAP on eBay (end time 06-Aug-11 12:24:57 BST)
I downloaded the SkyDemon SD trial and installed it on my PC. Connected up the GPS and pressed 'sync' in the SkyDemon program. Three other little tweaks:
1. I changed the settings in the GPS to load SD
skydemon.exe instead of the car satnav.
2. I had to create a device.xml file at skydemon.aero so that I could read the buttons on the screen.
3. I set the brightness to MAX in the GPS settings.
All-in-all it took about 15 minutes from unboxing to running the SkyDemon Mobile on my GPS.
Off to the car I went to test the screens visibility...
In bright sunlight it is quite difficult to read, but possible. In overcast light, the screen is perfectly readable.
I ran it in the car (in air mode) for a few days to get familiar with it. It is amazing, warning of buildings, warning of airspace and providing freq etc.
Battery life lasted 2.2 hours after the first ever charge and, in any case, works perfectly from the cigarette lighter cable that comes with the unit.
Next on to the plane. My wife and I flew to Peterborough Conington from Turweston. I had planned everything as per normal on my half mil charts and plogs. I also used SkyDemon to plan the route to check the accuracy.
Visibility was again good. Not excellent, but good enough. It was a real comfort blanket having it there as I knew I was well clear of ATZ, MATZ, Class D, C and A airspaces. Ooh and NOTAMs are all visible on the GPS.
One down side is that the GPS doesn't correct for wind, so you MUST still fly a wind corrected course. When you do that the GPS however, shows that you are pointing the plane off-track. Naturaly your instinct is to correct your course to point the plane on-track only to find that you drift.. off course, of course!!! It sounds obvious, but I'm just being honest!
My review... It's like having a mentor with you. Very comforting and most definitely worth the money. It's not a replacement for flight planning, but boy does it reassure you in all stages of GA.