Is it best to borrow or surrender the cash value in a universal policy?

That depends on whether or not you wish to continue having the life insurance in force at the insured's death. If you wish to have the life insurance in force at death, then it is best to borrow some of the cash value. If you surrender the policy, then you receive all the remaining cash value (less any surrender charges), but the death benefit is no longer there. Also the cash value received MAY be taxable.