Gryf thanks for suggesting my chip! You've got the v1 link in your post though.
For kv, Revere is right, RPM is what you're looking at. The trick though is to pair that kv with the right prop. Kv is to RPM as prop is to what gear you're in. For a car your Lamborghini engine might be able to handle 12k RPM but if you're in first gear you're not gonna go very fast. For your prop it's a combo of diam and pitch. Your prop pitch is the direct measure of how many inches it travels through the air on one rotation and is directly related to top speed. Diam is going to give you the punch speed, your thrust. So think of it like the bigger the diam the more torque you have, insta power sport plane feeling. The bigger your pitch the greater top speed.
High kv != high speed on its own. Your prop is just as important as the motor.
There are general guidelines of what kv goes with what prop, but it would be best if you tells us about your plane and then we can talk to that use case.