Balanced connections/cables are nice. They cancel noise induced into them because they have both a positive and negative, instead of a positive and neutral. Anything induced into the positive, gets induced into the negative, and so the noise gets cancelled when it reaches the balanced equipment. In short, it puts the noise out of phase with itself and therefore cancels it all together. With rca's, induced noise will get amplified downstream.
If you can get balanced equipment within your budget, I generally recommend it. Less noise problems, a higher magnitude (twice that of rca's) signal, and therefore a lower noise floor.