28TB Seagate External USB 3.0 Desktop Hard Drive – $300 | Seagate Deals

Anything over 20tb is a barracuda unless its old stock and then only the 20tb model. Everything else about it will not be EXOS. Performance from these is fine, maybe a little hotter than exos but no one knows how long they will run in a NAS yet really but the specs indicate they wouldnt last much past the warranty period if used fully 24/7

I got lucky with the 24TB Seagates from B&H Photo in January of this year being Exos for $280 each. However, I would have rather waited for these to get the extra 4TB of storage.

As other have said, these are likely binned EXOS drives that became Barracudas. They're loud and make lot of clicking noise on spin up, but otherwise they're fairly fast and run fairly cool once removed from their enclosure. If you plan to do heavy writing in the enclosure, point a fan at these since they'll get stupid hot at over 55C/131F due to the poor ventilation of the case.

Also if anyone is looking to shuck these, you can use this video guide to help get the hard drive out without damaging the enclosure.
https://www.youtube.com/watch?v=2-lH-EoNVwk

Most reports indicate these are Barracudas. But that those are just binned Exos. It's hard to know why they were binned as Barracudas but the basic hardware is the same. They likely just scored lower on some quality controls.