Chosen Solution
I bought a samsung 1 TB 970 EVO for my macbook pro, impulsively, after reading a verified purchase on amazon that some said it made their 2010 macbook super fast. Dan explained to me that it would not work, so I reluctantly returned it. I am planning on purchasing TWO 512gb samsung 860 PRO, which will cost me 20ish dollars more than the 1TB 970 EVO. I have a mid 2012 macbook pro , 2.5 ghz core i5. How can I combine the TWO 860 pro ssd’s with RAID and increase the speed with RAID 0? The speed difference between the PRO and EVO seem to narrowly favor the PRO, however the price difference HEAVILY favors the EVO. I have been around long enough to create my own belief (which may be wrong here) but with computers my words are almost always proven true - you get what you pay for.
You’ll need to stick with Sierra as it’s the last version of MacOS that offers RAID support at this time! High Sierra doesn’t work and so far Mojave doesn’t support it at all (it was pulled even in the docs!) APFS is the issue it can’t support RAID. You’ll need to stick with HFS+. In addition, the newer releases of Disk Utility have RAID support removed as an option for boot drives. Which is also why you need to stick with Sierra as the highest you can go with.