Clone Ubuntu to a USB 3 flash drive

Currently I have a laptop running Ubuntu 14.04 with a 256GB hard drive. I'm required to use a few Adobe programs so I fired up a VM (vmware workstation) and installed a Win7 in it. Unfortunately the performance is not as good, as it should be. I'm not sure if it's driver related or what ever. Anyway the easiest way for me would be to install Win7 back on the laptops hard disk (I anyway wanted to try Win10 ;)). Still I prefer Linux for development (and I'm required to use it for some stuff too). So much for the background.

I came up with a few solutions to install Win7 as main OS but be still able to use Ubuntu.

1. Dual Boot: not really an option since 256GB for 2 OS (I'd like to sync my Dropbox with both, that would take like 90GB per OS...) -> not an option
2. VM Host Win7, Guest Ubuntu: Should work but same issue as with Dual Boot.
3. Moving Ubuntu to a USB3 stick or external SSD. I'm thinking about a HyperX Savage SSD with the usb3 casing.

Will I be able to boot Ubuntu from the external drive if I just copy the disk with CloneZilla? or are there better ways to copy the OS and all it's files? I'm guessing, that the MBR/Bootloader will be copied too, what happens if I wipe the internal disk and install Win7 on it, do I just have to choose which OS to boot in BIOS (selecting the boot device USB or internal)? Or will this cause problems? Will I be able to boot my Ubuntu machine at any Computer with this set up or will it only work with my laptop (because of the hardware/drivers)?

One last thing, the disk is encrypted with the LUKS stuff, I selected full disk encryption during installation. In my opinion, CloneZilla should just clone every thing including the encryption. Am I wrong about this?

Solution 1:

I recommend you backup the list of installed applications, backup your config files in /etc, and your home directory, the just reinstall ( Windows first ). You only need 10-20 gb of space for Ubuntu, and you can keep your data files only on the Windows partition; there is no need to upload them to dropbox and download to the other OS too. Then restore your installed applications, config files, and home directory.