Graziano 12S Evaluation for Purchase?

[ACHiPo]

What are specific tests, measurements, or validation to assess a Graziano 12S in addition to basic lathe evaluation (runout, way wear, speeds, feeds, etc.)? It's my understanding that the 12S reduced the problematic electromechanical clutches of the 12, but it still has two clutches plus a brake. What is a good way to assess whether the clutches and brake work properly?

Does threading on the 12S rely on rapidly switching between forward and reverse? If so what is a safe way to test to make sure it works properly? If not, what's the best way to test threading functionality?

Thanks!