18TB Seagate Exos X18 7200RPM 3.5" Internal Enterprise Hard Drive (Recertified)

I've bought a few and have mixed feelings. One Exos definitely has issues calibrating during power-up. Unfortunately, nothing shows up on diagnostics, so I doubt I could get it replaced under warranty yet. I'm also having issues with another one but that may very well not be the drive's fault, so I won't hold it against them (yet). Also, got a WD Ultrastar that's dented but seems to work fine. The older Exos drive came with outdated firmware.

If you're going to buy from them, I'd suggest going with the WD/Hitachi Ultrastar. Seagate drives just seem too failure prone. It's not unusual to find them selling the WD drives for the same price as the Seagates. I've seen them sell 18TB Ultrastars for $185.

Be aware that some WD drives have the Power Disable feature, which makes them harder to use with many power supplies. SPD is nice, in that they include a SATA power adapter and a small strip of Kapton tape. I'd use the Kapton tape, as that style of power adapter has been known to spontaneously catch fire. Or, avoid the issue altogether and buy a model that does not have the Power Disable feature. You can tell which drives have it by the second-to-last digit of the model number. If it's a "0" it has the Power Disable feature. If it's an "L" (Legacy) it does not have the feature, so you won't have to worry about it.

Also, be aware that these are all enterprise class drives. They will be louder than consumer drives, especially the seeks. How bad it is seems to depend greatly on the case it's mounted in. Vibration dampening mounts make a HUGE difference. If directly mounted to a metal drive cage, be prepared for earthquakes. The Seagates may be a tiny bit louder than the WDs. Also, despite being of similar design, the WD Ultrastars have significantly louder and faster seeks than the ones they stick in the Easystore/Elements line.

If you wish to adjust advanced features, you may want to become acquainted with Seagate's SeaChest utilities (not to be confused with SeaTools). I have not been able to find a comparable utility from WD. Luckily, many of the SeaChest utilities also work with the WD drives.

One major reason I bring this up is because they can be used to adjust power management settings. The Exos line does not support conventional APM (Advanced Power Management) which is what most generic utilities adjust. The Exos drives support EPC (Extended Power Condition) and Seagate's PowerBalance. I find the defaults a bit too aggressive. You can use one of the SeaChest utilities to adjust the timers for reduced drive electronics, head parking, reduced spindle speed, and complete spindown. I think the first two are the only ones enabled by default.

The WD Ultrastars support both APM and EPC. The SeaChest utility does seem to be able to adjust EPC (and presumably APM) settings on the Ultrastars. Interestingly, it does not work on shucked Easystore/Elements drives, despite reporting the settings as both changeable and saveable.

Both drives support TLER/ERC. By default, it is enabled on the Exos, with a 10 second timeout. Oddly, the WD Ultrastar seems to have it disabled. Even more oddly, the Easystore/Elements drives have it enabled, with a 7 second timeout. It can be enabled/disabled or adjusted on all of them. Unfortunately, the settings do not seem to persist through power cycles.

As others have noted, the packaging is phenomenal. Also, the SMART data is wiped and some (maybe all) only show the recertification date, not the original manufacture date.

Anyway, those are my comments. I know that's probably way more than most people care about.

I purchased 3 times from them, 4 manufacturer recerts drives. WD HC550 18TB though. The packaging is top-notch and comes in sealed antistatic bags. Looks brand new. The manufacture date of all drives is 2023. All passed pre-clear/post-read on Unraid. Make sure you do some kind of extended test since the warranty is only 2 years.

I'm holding out for the 20tb to be under $10/ TB