I have a bootable USB flash drive that I made with YUMI http://www.pendrivelinux.com/yumi-multiboot-usb-creator/
I can make a backup image but when I restore the image the drive isn't bootable. The same thing happens if I try to clone the drive to another flash drive. I've tried every setting I could like the sector-by-sector backup, selecting the MBR as part of the recovery, etc.
I found another utility that let me clone my flash drive to anther one and it was bootable. I really want the features of True Image such as making backups, restoring to different sized flash drives, etc.