Hi, I have a Western Digital Thunderbolt Duo configured as JBOD, and I am going to replace those hard disks with two 512GB SSDs - installing one SSD with Mavericks and the other with Yosemite. I want to do this because I want to try out Yosemite for, say, 3 months first. I would like to have the iMac internal Micintosh HD keeps storing my emails, iPhoto library, iTunes library etc. But would this cause files out-of-sync issues? For example, if today I use Mavericks rip a CD and tomorrow I use Yosemite, will I still see the "new songs" in iTunes? Thanks.