I know that a good reason to store backup images on an external hard drive vs. an internal hard drive is to safeguard against the possibility that your computer will for some reason (virus, theft, lightning, etc.) become unusable. My backup plan includes storing images on my external HDD, but I also like to store images on my second internal HDD, which I do for two reasons that may or may not be right. If I am wrong will someone please correct me: 1) Imaging to and restoring from an internal HDD is significantly faster than an external (USB connection in my case) HDD. 2) There's a lower likelihood of I/O errors when imaging to and restoring from an internal HDD vs. an external HDD. Thanks for your advice.