What should i be concerned about when powering a 10A load from 120VAC
25 feet is about 8 meters, which is about 8 microHenries. For a single wire.

But power cords have the return wire about 5mm away, so assume 10:1 reduction in inductance, or less than 1uH.

How much effect on your power?

Impedance (like resistance, but for changing currents) is computed as 

Zl = 2 pi * frequency * inductance

Zl = 6.3 * 60 * 1e-6 = 377 e-6 = 0.000377 ohms

At 25 amps, you will have (v = I * Z) 25 * 0.000377, or
less than 0.01 volts, or about 0.01% reduction in voltage.