Qwen3.8 125B (6B active) Flash-Next

User shares a MacStories review of the M5 Ultra Mac Studio 256GB and a DeepSeek V4.1 Flash comparison against 2x DGX Spark. Qwen3.8-Flash-Next runs at 108 tok/s on a short prompt and 143 tok/s for code generation on the Mac in MLX oQ4e, versus 42.6 and 39.0 tok/s on 2x DGX Spark in NVFP4 TP2. Prefill is 2,057-2,887 tok/s with TTFT of 24.4 s at 64K, 50.0 s at 128K, and 104 s at 256K. Decode decays from 90.7 tok/s at 4K to 74.7 tok/s at 256K, and combined throughput rises from 66.2 tok/s at 1 stream to 81.5 tok/s at 3 streams. The comparison is not a controlled A/B: the Mac runs oQ4e on MLX/oMLX while the Sparks run NVFP4/FP8 on vLLM/SGLang.