So far I love it. I bought it brand new from Lenovo and you could pick from I think 3 or 4 distros. I picked fedora, which it came with 38. When I first booted up it had a bios update which honestly surprised me that they would bother. Then upgraded to 40 through the fedora upgrade path. All painless.
I was fully prepared to make a windows live USB just to flash the bios/firmware.
I just bought a Thinkpad x1 carbon preloaded with Fedora and it’s pretty fantastic.
I had one quite some time ago so my memory is probably not perfect here. it was almost good enough for most things. I feel like there was an issue where it only had 32bit support for some stuff, but this was years ago.
I do remember it had decent support for Ubuntu out of the box.
It had a ton of bios updates when it first came out, so step one is I’d go make sure you’ve got at least a recent version.
Battery management