The problem with the brake feature on many of the less advanced ESC's is that you can only adjust it in relative coarse steps. In most cases the brake is too strong and will stop the propeller turning, which will not give any significant slowing down of the model. We want the ESC to be able to brake the prop so that it compares to a low idle when going downwards, this will give maximum braking effect. If the brake is too weak or disengaged completely the prop will be allowed to spool up, and although more effective than a stopped prop it will not give the desired braking effect. This is where the finely adjustabe F3A brake comes in handy, since you will be able to adjust the amount af braking to your liking.

Depending on the ESC the F3A brake can be adjusted via a prog-box (Hacker/Jeti Spin), via a prog card (e.g. YGE), via a PC interface (Castle I think...?) or via the throttle curve (Schulze). In the first three cases you will have to try different percentages between flights to fine tune the braking to your liking. On the Schulze you can use the gas trim-lever to adjust the amount of braking in the air since it works a bit differently. Chad has described this in detail in another thread here on RCU.

When using an F3A brake you will be able to get plenty of braking on an outrunner as well.