512GB Mac Studio runs Qwen3.5-397B but lags

The 512GB Mac Studio is the definitive "local muscle" machine for AI practitioners, but parameter count doesn't solve the speed-quality trade-off for iterative work.

• –Loading a 397B parameter model at Q8_0 requires nearly 400GB of VRAM, making the 512GB Unified Memory setup one of the few consumer-accessible ways to run it.
• –In-process caching remains a critical friction point; without optimized prompt caching, the feedback loop for coding is too slow to compete with smaller, faster models like Claude 3.5 Sonnet.
• –The "muscle-and-agent" split—using the Studio for reasoning and a separate Mac Mini for orchestration—highlights a shift toward multi-machine local-first developer workflows.
• –Quality-over-speed is the user's priority, yet even with 512GB, the "technician vs. practitioner" gap persists as software optimization lags behind hardware capacity.