Optical or 6 channel direct (3 cables) for speakers?

Question

I am currently using 6 channel direct on Logitech Z-5500, my new soundcard for my laptop supports Optical Out and Logitech Z-5500 has Optical input. Which one has better sound? If optical is better, is it worth the money for the cable? I only need a foot long optical cable

Answer 1

Just use the optical.