What are the advantages of using UART/Mavlink over PWM on Storm32 Gimbal controller?

I have a Storm32 BGC that is currently connected to my Navio2 board by PWM input on RC9 (tilt) and 10 (roll)

I would like to know if there are any kind of advantage to use UART/Mavlink protocol instead of standard PWM communication. Arducopter documentation is quite vague on this specific point (“could bring additional monitoring capabilities”)

Thanks for your views