What external SSD hard drives can be used for a Ubuntu install?

I have previously installed Ubuntu on both a USB stick and an SSD drive connected through USB. Nevertheless, I have failed to do so recently with the SanDisk Ultra Portable SSD external hard disk. The reason seems to be that a boot partition can’t be created on this disk (if anyone knows otherwise please leave me a comment). Neither will such installation work on any USB stick; it works on some but doesn’t work on others. I very much need such a portable installation on a (rugged, portable) external SSD of at least 250GB, ideally 500GB. Does anyone have any experience with what works among those currently available (Western Digital, Seagate…) ?

Same question for currently-available USB sticks. I’m genuinely more interested in knowing what are the USB drives that would work than in workarounds trying to fix the install on the SanDisk, although the latter is also an option.