Yes, I'm also looking at the
TerraMaster TD2 Plus Thunderbolt 3 RAID Storage Dock
https://www.terra-master.com/global/td2-thunderbolt-3-plus.html
YouTube review here
According to the review
1) It only supports a max 16TB capacity for each HDD making the dock's max capacity as 32 TB. However, its compatibility chart below says it supports a max of 20TB per HDD making the max capacity the dock can support as 40TB
https://www.terra-master.com/global/compatibility/
2) Beware! It seems not running at TB3 speed for the HDDs are recognized as USB drives as with the USB controller. In short, the HDDs are operating at USB 3.1 speed on the TB3 bus. So, misleading to say it's running at TB3 speed
PRICINGS
Price of the TerraMaster TD2 Plus Thunderbolt 3 RAID Storage Dock + Seagate IronWolf Pro 20TB NAS Internal Hard Drive HDD – CMR 3.5 Inch SATA 6Gb/s 7200 RPM 256MB Cache
Price = US$830
For 40TB storage you just need to add another US$500 Seagate IronWolf Pro 20TB HDD will do. As for the other options, you need to buy another totally new dock to make up for 40TB storage which doubles the price
Other options are
1) SanDisk Professional 20TB G-Drive PRO - Enterprise-Class Desktop Hard Drive, Thunderbolt 3, USB-C, 7200RPM Ultrastar Drive Inside - SDPH51J-020T-BAAD
https://www.amazon.com/dp/B09WFV1PBY
Price = US$900
2) LaCie 2big Dock RAID 20TB External RAID Hard Drive HDD with SD Card CF Card Slots, for Mac and PC Desktop Data Redundancy Thunderbolt 3 USB-C USB 3.0
https://www.amazon.com/dp/B075C6WHCC?th=1
Price = US$1027
