I am running a 2013 iMac with only a 256GB internal SSD. I just keep the OS and Apps on there. I also use a 3TB WD MyBook external for all my other files. My question is - should I encrypt the external drive? I like the peace of mind knowing my stuff is secure in the unfortunate event it is stolen, but I have also read about it hindering the performance of the drive with slower read/write speeds. I am just wondering how many of you encrypt your external drives, even if they never leave the house? If you do encrypt the drive, do you notice a difference in speeds?