C172 Flaps up or 10 degrees for takeoff

An interesting dilemma.
The manual for the 172 N tells you that 0-10 degrees is acceptable for
takeoff. However it does not tell you what affect it has at low altitude
300 feet MSL Density altitude around 2500 MSL. It only states that it
will have a detrimental affect at high altitude on a hot day. It also
does not give an airspeed for Vy flaps 10 degrees.

In talking to another pilot who has an 172 L has states that his manual
says if 10 degrees flaps are used it will decrease ground roll and
decrease climb rate. Having an overall detrimental affect.

The only definitive number the 172N manual states for flaps 10 degrees
is Vx.

First hand experience seems to confirm what the 172 L manual says.

What do you all think?
Michelle