Before I get my Mac I want to back up my current PC hard drive complete onto an external drive. Is it possible to use that same external drive to back up the data on my new Mac once it has been configured with all the data from my current PC? In other words, after I take my PC to the Mac store and they copy all that data into my Mac, can I keep the PC backup on the same external hard drive that I will be doing my regular Mac backup on? Can I format 2 500GB partitions on a 1TB external drive and leave 1 partition with the PC backup and use the other partition to be my daily backup for the new Mac? Thanks.