Just food for thought. I use 7:1 in Fore Flight. The glide path ring gives me a conservative assessment of what is around me and where I can go. In a real situation when you have to transition your mindset from power flight to glider, wind conditions, maybe distracted by emergency procedures or looking for a suitable LZ so your airspeed is off etc. you loss time and altitude quicker then you might if you were practicing an engine out procedure.