First off, we'd like to point out to you that the 2slots SSD enclosure is normally being used in Software RAID 1 setup, where more secure data management over performance. Where user(s) is foregoing speed for more secure data management capabilities. Maximum Read/Write speed would be at about 1400Mb/s when in a Software RAID 1 Setup, as the speed for each SSD Slot would only be at X2 speed each. (see link for difference between RAID 1 & RAID 0: https://www.trebleet.com/raid-1-vs-raid-0 )
Also, even with RAID 0 setup (when we're combining the speed of both SSD slots, X2 speed times two, getting a full PCIe3.0 X4 speed, where normally Read/Write speed would be at about 2800Mb/s). By doing so (Software RAID 0 setup), you'd only get full normal PCIe3.0 X4 speed with 2 SSDs installed. As each slot is allocated with X2 speed. Just to make sure that you're aware of this.
IF you're looking to have a single SSD enclosure that works full PCIe3.0 X4 speed (You'll be getting 2800Mb/s Read/Write Speed), then you may either go with the：-
Also, we're attaching a generic message that we send to all our SSD Enclosure, Mac Mini Dock, Dock station customers. It includes lots of useful information, you may want to have a look at it if you've got the time to.
Are you a Mac Mini Dock / 8in1 Dock / SSD Enclosure customer of ours & also an M1 chip computer user?
If you are, you might want to take a look at the SSD compatible list attached. Especially if you're looking to purchase an SSD that would be used in a Mac OS environment / with an M1 computer. As there are numerous reports of M1 computers do somehow limit the WRITE speed of an SSD while the READ speed is normal. We strongly believe that the issue would be corrected in the next Mac OS update, hopefully. Do note, even the SSDs listed as "COMPATIBLE" ones, the WRITE Speed might still be limited / degraded if used with M1 computers. We suggest that you have a look at the forum links below before getting your SSD for storage expansion.
Should you decide to try out the "Compatible" ones on the SSD compatible list to see if it works without the WRITE SPEED LIMIT on an M1 chip computer, please do purchase the desired SSD(s) from an SSD seller that allows return if the purchased SSD(s) is somehow under-performing or showing lowered WRITE speed due to M1 chip WRITE speed limitations. We do not accept product return if it's solely for the reason of WRITE Speed Limit on an M1 chip computer. In which it's something that Mac's end should be rectifying.
So far, we do know that Samsung 970 Pro, Samsung 980 Pro, Corsair MP400 SSDs are working well and not affected by the WRITE speed limitation on M1 computers.
NVMe Slow WRITE speed on M1 computers - https://www.trebleet.com/forum/technical-support/nvme-slow-write-speed-on-m1-computers
DO NOT use Sabrent SSD in MacOS environment - https://www.trebleet.com/forum/technical-support/do-not-use-sabrent-ssd-in-macos-environment
Tested the speed of the internal SSD of a Mac Studio with M1 Max chip - https://www.trebleet.com/forum/tb3-mac-mini-dock/tested-the-speed-of-the-internal-ssd-of-a-mac-studio-with-m1-max-chip
Latest SSD Compatible List - https://www.trebleet.com/forum/thunderbolt-3-usb-ssd-chassis/latest-ssd-compatible-list
Mac Mini Dock User Manual - https://www.trebleet.com/forum/tb3-mac-mini-dock/mac-mini-dock-user-manual
What is the allowable SATA drive slot dimension & size on the Mac Mini Dock? - https://www.trebleet.com/forum/tb3-mac-mini-dock/what-is-the-allowable-sata-drive-slot-dimension-size
Can I use an SATA M.2 SSD in the Mac Mini Dock? - https://www.trebleet.com/forum/tb3-mac-mini-dock/can-i-use-an-sata-m-2-ssd-in-the-mac-mini-dock
Do I need to turn off / switch off my MacMini Dock after I've shut down my MacStudio (or other types of connected device)? - https://www.trebleet.com/forum/tb3-mac-mini-dock/do-i-need-to-turn-off-switch-off-my-macmini-dock-after-i-ve-shut-down-my-macstudio-or-other-types-of-connected-device