Rejected the TOC. Made a meticulous image report that showed careful unboxing and setup.
There was a line in the TOC that (from very vague memory) disallowed using the OS for a.o. nuclear power mgmt. I did work in energy back then (but mostly webdev), so I could not rule this useage out. Send it along to Redmond and got a prompt reply from som e salesman for some kind of "industrial licence" for insane amounts. A few back and forths later, I got a measly €20 Euro's back. They put the rest down to admin fees, and OEM discounts.
Anyway. It ran SUSE and (k)ubuntu perfectly.
I guess it's much easier nowadays. But I buy my laptops preinstalled nowadays. Open the lid, answer five or six questions, restore my backups (/etc, .files, ~), reinstall the packages from packages.txt, reboot and continue working.
Unfortunately it's in Italian, basically if you don't accept windows (and office) tos you can be refunded, almost nobody knows this except some Linux users. However, if you follow the steps (such as not accepting the tos) you're basically guaranteed a refund or to win the legal dispute