Good idea to keep a copy on both. RB will access the SEQ file faster on the main drive, also if you have a USB 3.0 port you can get a USB 3.0 2.5" Hard Drive case as the BIAB is only USB 2.0, if not and your DVD drive has a SATA connector on it you can get a DVD SATA Hard Drive Bay and put the BIAB Hard Drive in that and get a USB case for you DVD drive, that will give you great access speed.