From NAS compares:
Seagate 16TB Ironwolf and Ironwolf Pro NAS Hard Drives Revealed
Seagate 16TB Ironwolf and Ironwolf Pro NAS Drives Revealed - ST16000NE000 and ST16000VN001 Good news for those looking maximum storage in both small and large NAS drive enclosures, with the announcement that the Seagate Ironwolf NAS hard drive series is going to be available in a staggering 16 Teranascompares.com
The 5-year warranty on the ST16000NE000 16TB Ironwolf Pro NAS
Seagate's warranties are very difficult to find: "length of time indicated as part of your product packaging". The product packaging says the exact same thing. You have to look it up by serial number.
Checked the warranty on 1 of my IronWolf Pro disks and it is indeed 5 years. It also includes data rescue, which I suppose accounts for the higher price. These things tend to be disk specific so don't know about other Ironwolf Pro versions.
I cannot comment on the IronWolf pro, my comments are on the IronWolf., which for me, have been garbage. Considering my horrid experience with IronWolf, I want nothing to do with the pro either. Exos, have been fantastic. If the IronWolf Pros are better, that's great.