Preemptively, because I've seen some concerning blue-screens, I'm wanting to make some Recovery Media using the HP Recovery Manager, and I've noticed it limits to only one being created and accepts only multiple DVDs or a flash drive.
To save myself burning endless DVDs I'd likely lose, I'd prefer to use my one and only 32GB flash drive, however I'm not happy to be rendering it useless except for this one purpose and you can't trust USBs to not die on you in any case.
So if I were to choose the USB option, and create the Recovery Media, but then use Win32diskimager and copy to and store the 32GB image on a spacious HDD, I'm wondering if I'd be OK to then format my flash drive and simply write it back to my USB if I ever need to.
I have never tried your scenario myself and I can't be 100% sure it will work.
It will work if you create initially the HP recovery media on a USB drive and then create an image of the entire USB device - and store this image on the HDD. You can use 3rd party software like CloneZilla for this image of the USB device. Eventually, unpack the image of the USB pendrive from the HDD to the pendrive itself and last, use the pen drive - this will work 100%.
However, if you want to, you can initially use CloneZilla - free, small and oper-source utility - I have used numerous times without issues. CloneZilla allows you to create system images or clones of HDDs and it supports storing them on HDDs (even external USB HDDs) - not only USB pendrives.