I have a brand new late 2013 13" rMBP. I intend to run some VMs on it at times and I'm debating how best to store them, I believe my options are: Save them on the SSD Save them on a USB 3.0 Hard Drive Save them on a USB 3.0 Memory Stick Save them on a 64/128Gb SDXC Card Is there a way I can evaluate how these options compare in terms of performance? To save SSD space then a USB 3.0 drive/stick is an obvious option but I'd prefer not to be connecting another device (and risk accidentally disconnecting it which really seems to upset a VM). Is an SD card a viable option for storing a VM Image if needed? Does the speed compare to USB 3.0? Thanks, Chris.