What do you guys think about something like this?

kernel_save = "%s/%s%s" % (download_root, kernel_short, "_koan")
initrd_save = "%s/%s%s" % (download_root, initrd_short, "_koan")

that will keep the installed kernel/initrd intact.
Do you see any bad sideeffect?

Provided the right arguments are still given to the bootloader config, this looks totally fine.

--MIchael