Hello, I plan to buy an external drive to back up the up-coming MBP 2016. I suspect that the maxed out model could be 1TB or more. What do you think? It also seems that there will be no usb port on the new computer. Shall I still get one with old usb port and buy an adapter? I guess if I use TM to back up, 2 or 3TB might be good. If I use CCC or other software to clone the internal drive, the backup drive should be equal or just slightly larger than the internal drive. Am I right?