Hello everyone, I am thinking about upgrading my macbook with a dual hard drive system. I already place my Crucial M4 SSD (256gb) in it and may replace the optical drive with the HD enclosure. I am curious for those who have a dual hard drive system, how much of a significant change was the battery life? Is it better for me to just store my music and files into the SSD and don't worry about adding the HDD? oops I meant to say Dual Drive (SSD and HDD, not 2 HDDs) in topic.