To clone a virtual system with a 20GB HDD from a computer using USB2, I use huge flash drives. The process takes 4 minutes to complete when using Silicon Power to copy archives to a USB flash drive while simultaneously archiving with a Rar profile (high-speed archiving, split into 150 MB volumes), and 6 minutes while using Transcend. Both flash drives have the same feature, but are 2 times faster on a device with USB 3.
32GB SanDisk USB Flash Drive (SDCZ430-032G-A46)
78 Review
Sandisk Ultra Flair 128 GB Silver USB Flash Drive: Reliable and High-Speed Storage
65 Review
Compact and Convenient: SanDisk Cruzer Fit USB 32GB Flash Drive (SDCZ33-032G-A11)
66 Review
Titan Gray Samsung BAR Plus 256GB USB 3.1 Flash Drive (MUF-256BE4/AM) with Up to 400MB/s Transfer Speed
69 Review
8TB Seagate Backup Plus Hub Desktop Hard Drive with Data Recovery Services
56 Review
18 TB External HDD Western Digital WD Elements Desktop, USB 3.0, black
95 Review
π Seagate Expansion 3TB Portable USB 3.0 External Hard Drive (STEA3000400) in Black
60 Review
Game console Microsoft Xbox One X 1000 GB HDD, black
53 Review