External drives work great with DVDFab and Passkey for all disc formats. You can set either product to ignore certain drives as well if you find that necessary, so no problem either way! I use the LG BE16NU50 USB drives, be sure to check the read speed specs before purchasing a new one. If you have any interest in using Fab with 4k UHD discs, make sure to get one that has UHD Friendly firmware or can be downgraded if necessary.