Qwen3.8 27B

User reports Qwen3.8-27B at 42.2 tok/s single-user on one DGX Spark, with prefill at 2,158 tok/s. Setup is vLLM with unsloth's NVFP4 weights on the GB10's FP4 tensor cores, plus DFlash2 speculative decoding with 10 drafts from an NVFP4 drafter and a small vLLM plugin. At 16k context it reaches 33.4 tok/s and at 100k 29.5 tok/s; the board's 16k two-user test gives 60.6 tok/s total, first among single-Spark entries. Quality checks against BF16 recover 99.3% on gsm8k, 101.1% on ifeval, 99.4% on humaneval and 101.2% on NarrativeQA.