The seagate is confirmed to have an Exos drive in it, newer production dates past about 09/23 are all getting st14000nm0121 mach2 drives (2 actuator heads, 2 platters). I got one and after tests (put a fan on it while in enclosure, runs up to 60c otherwise) shucked it. I can't comment on the noise while it's sitting in the array with the others, but I can tell you that it does seem to run a couple degrees warmer than the last seagate I shucked (an Ironwolf pro).

The WD will probably produce a white label ultrastar. Nothing wrong with them, just not as good of a price/deal. Also consider return policies: bestbuy is easy if it fails the initial tests, you take it back and swap for a new one. Newegg you need to do rma/return shipping, it's a hassle. WD direct might cover return cost, but it's still shipping downtime.