Factory headstuds, most people I know won't reuse them. ARP says you can reuse theirs 2 or 3 times, which I guess speaks to both theirs and the factory ones.

However I have no personal experience with them like ASE Tech has/does, so take that with a grain of salt. I personally would not use factory ones after pulling them off, but that is a Nissan motor and I am OCD like that.