The reason why I think the Evo 850 is not a bad choice for the OP is because of the use of Logic Pro X. If you're doing simple editing of 16-bit, 44.1Khz files, a slower SSD or fast HDD may be OK. But more sophisticated editing, higher-res files, use of samples or real-time recording would tend toward a faster SSD. But asking about the fine points about the OP's use when they're willing to spend the extra money didn't seem worth the time and effort to get into.
The cable should work OK. However, I would suggest something like the following, which is what I bought:
https://www.amazon.com/Inateck-Inch...5581380&sr=1-1-spell&keywords=inatech+usb+3.0
It's actually cheaper than the cable and provides more protection, both from dropping it and inadvertently disconnecting the cable. If you use it with a HDD, it provides protecting against shorting the exposed underside. It may seem that prep'ing the SSD would be a one-time use, but disk enclosures can prove useful in the future, especially if you're in a household with multiple people using multiple computers.
I don't read the thread on what SSD people got - it's too long. I mainly read the El Capitan, Mac Mini and MBP forums and I don't recall people having issues with the Evo 850. You might get a bad one, but if you buy from someplace with a good return policy, you should be OK. Having a couple of the Evo 850's in my 2012 MBP, if you have a properly working Evo 850 and 2012 mid-MBP, you will be OK - there are sometimes a problem with the cable, especially if the MBP dates from 2012 (it's a ribbon cable, not a typical wired cable). Compared to installing a SSD in the Mac Mini (I've done it with my 2012 and 2014 models), installing a SSD in the 2012 MBP is a piece of cake. Check the installation guides on iFixit or OWC to see if you feel comfortable in doing it.