I've used King Schools for my Instrument and a few other add-ons such as Garmin G1000, G430/530, Commercial/CFI maneuvers, and I've always been impressed by the content from the producers. I tried other competitors content for other phases of training and just feel more comfortable with King's material. I know King's offers a lot of other content, but I'm glad to see that they're offering free products for some of the important phases of flight (like Air Marshalling), sometimes taxiing into bigger airports is stressful, this made it easier to understand the process and what to expect. It's one thing to read directly from the AIM, but a video format and interactive material makes the difference.
Brady F.
02/02/2021
Understanding Aircraft Marshalling Signals