What do you think is best glide speed Sean?
I would imagine that would be C/L max. Which is also going to be Vx.
I really do not understand how C/L max would be the best glide speed in any airplane. The lift to drag ratio should be at a maximum (L/D max) to provide the best glide speed. At C/L max, even though parasite drag is low, induced drag is very high, and therefore this does not give you the most lift per amount of drag.
Only in an engine with a powerplant that delivers constant thrust with changing airspeed. A C172 doesn't quite fit that description, unless you have the turbojet STC.
What did you mean by this bookworm? That in these airplanes that you describe C/L max is the best glide speed, C/L max is Vx, or both like FE hoppy said?