Can attest to the X1C7 drain when shut down, although to a lesser degree. I have it as a secondary machine for Windows, so I’ll sometimes leave it alone for a couple weeks. It’s completely dead by the end of the month unless I go into the BIOS and disable the battery until the next charger connect. You wouldn’t ever know from normal use, it still lasts around 6 to 6.5 hours on a full charge.
Has anyone gotten it to integrate nicely with LUKS and secure boot? Cursory search on the topic looks like a nightmare. I could live without secure boot, but I’d much rather sacrifice battery life than save to an unencrypted swap.