Hi Guys - I'm new to Mac so please bear with me as I come up a steep learning curve! I just moved from PC to a Quad core iMac and with the PC I had two external 1Tb HDD's formatted as NTFS. These contain all my photo images on one and the second is sync'd to it daily as a backup. I got the Tuxera app to allow me to write to the drives but my dilemma is how to sync them since reformatting is not really an option as there is around 750Gb of data and I will still want to share with PC from time to time. Is there a sync/clone app that will allow me to regularly sync my main external hdd to the secondary one? Thanks in advance for any guidance you can give me.