OpenRouter reported that DeepSeek's new V4.1 Flash model processed 1 trillion tokens in its first day on the platform, putting it on pace to be the largest paid model launch OpenRouter has tracked over its first 48 hours. Ninety percent of those tokens were served from cache, and the effective price came out to roughly $0.006 per million tokens, about five times cheaper than GLM-5.3 Flash. That combination, heavy cache reuse plus a low headline price, is what actually drives adoption at this scale rather than benchmark scores alone. A model can top an intelligence leaderboard and still see little real traffic if it is expensive to serve at volume. DeepSeek V4.1 Flash's first day numbers are a market signal that the model is genuinely cheap to run in production, not just cheap on paper, which matters more to teams choosing a default model than another round of benchmark comparisons.