Do you really need rim locks?

I just ordered some Pirelli xcmh tires. Was tired of not getting the offroad responce that the bike needs. I was wondering with that aggressive of a tire do I need rim locks. I mostly ride steep trails and some rocky stuff so I never air down the tires. What's your opinion?

I would use rimlocks below 15 psi. Much better traction around 9-12 psi including rocks.