In the case of the Astros, all of the different winds are effectively identical motors with identical efficiency, power and torque. What varies is the Kv, but an inverse relationship of voltage and current in the same proportions gets you to the same end result, since the motor limits are rpm and temperature. Miles shared a link with a performance chart listing each winding of an Astro 3110 that displayed this commonly misunderstood relationship very well. I tried searching and couldn't find a link for you. The bottom line is that as long as the copper fill is the same, the motor is identical.
In the case of hubmotors, the inability to vary gearing due to limited wheel sizes along with the practical limits of voltage means you can't effectively consider different windings of an otherwise identical motor to be the same motor like you can with RC type motors. For hubmotors the higher turn count motors with the lower Kv are slower and lower power, and the will often be more effective on hills and in stop-n-go traffic because they are more efficient at lower speeds. Higher Kv hubbies are faster and higher power because they are can handle greater current resulting in the same torque but at higher rpm, so greater power is possible with the same voltage limitation.
John