I was thinking USB 3 and a Samsung 850. Don’t want to spend hundreds on a Thunderbolt enclosure. What do you think?
Adapter cables from SATA to USB or Thunderbolt (etc....) would be sufficient. Why bother with an enclosure for a SSD?
SSD drives have no exposed electrical contacts other than data and power. So you could set the drive directly anywhere and just use a small power supply (I use a 2 amp small power adapter that plugs into my drive and then the wall). Then run an adapter cable from the SATA to whatever port you choose to use on the Mac.
Much cheaper option.
In my case, I'm just going to USB 2.0. And honestly, it's just as fast as my built in SATA-2 connection for booting.
I'm sure benchmarks would disagree with me. But I'm just looking at perceived performance.
Now, comparing USB 2/3 to thunderbolt may be significantly different. But I don't have a thunderbolt machine to compare.
If you want scientific data, I'd google something like the following:
'Compare data transfer speed USB 3 and thunderbolt'
And:
'Compare data transfer speed SATA 3 and thunderbolt'