Here are the three main differences between F3 and F4 flight controllers for drones:

Speed and Power: The F4 controller is faster and more powerful than the F3. This means it can process information quicker, leading to smoother and more responsive drone flights.

Advanced Features: The F4 can handle more advanced features, like better filtering and higher control frequencies, which the F3 can't manage as well.

Long-Term Use: The F4 is more future-proof. It can easily support new updates and features, while the F3 might struggle with newer technology over time.

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