Medusa Afterburner V2 BL motors

I have read only good things about medusa 60mm motors in revo's and buggy/ truggies.
I know larger can motors will have more torque, but if the 60mm motors seem to be doing well, what would the benefit be of larger cans?

I am currently building a revo which will be running 10s and a 1000-1100kv motor and a muggy on 6s which will be running 1600kv. Both cars will be geared for 40mph. Which size can would suit each car best? I was thinking 36-60-1100 for the revo and 36-70-1600 for the muggy?