Do you mean the servo mounts or motor mount?

As for the alu motor mount i haven't used an alu motor mount cause it isn't needed.
It's better to use the plastic one with the plate that goes between motor mount and motor.
I wouldn't recommend the alu one without using the plate that goes between it.
When the alu motor mount is used and it gets to hot the heat will be past on to the plastic tub and could melt with more slop on the motor mount and this could distroy the gears.

As for the alu servo mounts i can recommend to use the RM-01 type servo mounts, they will bring the servo 3mm more forward and gives more space between motor and servo.
Can only be used with using a trunbuckle from servo to steering.

Hope this helps