If the GPS is for use in the USA then SkyDemon would not be the best choice. The US charts are really not good enough as they miss a lot of essential sectional detail. In the USA Foreflight is the best choice for a PC/Tablet/IPad/etc. solution at the moment.
If you are considering a dedicated portable GPS unit then I prefer the Garmin 696 over the 796 as I find the touch screen of the 796 a hindrance in any type of turbulence. The Aera 560 is nice if a smaller device is more suitable. If you go the Garmin route make sure you get an XM Weather capable unit.