Can local quantized weights on Apple Silicon replace metered frontier APIs on high-stakes production QA gates? We ran 18 deterministic enterprise reliability gates across Blind-Solver Answer-Leak Detection, Refusal-Aware Prompt-Injection Grading, and Dirty-Ops Multi-Timezone JSON Extraction comparing local 4-bit MLX models on a 256GB Apple M5 Ultra against Claude Sonnet 4.6 and GPT-4o over HTTPS.
| Model / Runtime | Tier | Accuracy | Suite A (Leak) | Suite B (Inject) | Suite C (JSON) | False-Pass Rate | Median Latency | Throughput | Cost / 100k Runs |
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