Hi Guy, i see 3PK can change to HRS with 2 servo digital, it make servo works faster and stronger, and in HRS mode we can use fail-safe on reciever.
And i am using M11, and it can't change to HRS, it don't have fail-safe ..., and i don't know servo user with M11 as fast as 3PKS with HRS, isn't it?

I ran airtronics servos digital and non digital with my m11 and had no speed issues
If your running electric it all depends on the output of the esc's bec
I did switch to m11x and with hrs the servos react quicker
But both feel the same in standard res....in my opinion