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

User compares R9V and Strata running Qwen3.8 Flash-Next UD-IQ4_XS on a dual Radeon AI PRO R9700 system with 96GB DDR4 and an AMD 3900X. R9V is 15-18% faster on prefill at every context size, while decode is roughly level between the two engines. Setup is R9V v0.4.4 with UD-IQ4_XS GGUF shards and MTP, single-session requests at 16k, 32k and 64k context with 256 output tokens. Strata v0.1.39 ran on a single GPU because the two-GPU split needed about 118 GB of RAM; its expert cache held 10,774 experts in VRAM with a 98.7% decode cache hit rate. R9V measured 1166 tok/s prefill and 57.3 tok/s decode at 16k, 1156/58.8 at 32k, and 1109/53.8 at 64k. Strata measured 980/53.3 at 16k, 1003/53.8 at 32k, and 986/54.6 at 64k. The host has 92 GiB of RAM against the R9V README's 128 GiB, and the README's claimed 1.6-1.7k prefill was not reached.