What Landed
Matthew Berman argues that DeepSeek V4.1 Flash, an open-weights multimodal model, offers the best mix of quality, cost and speed available. He concedes that Opus 5.5 still beats it on harder builds such as the Fall Guys clone. His main number comes from Artificial Analysis: about $0.26 per completed task, against $211 for Kimi K3.1 Pro and $763 for Claude Fable 5.1 Max. He also ran a 50-minute autonomous coding job entirely on a local DGX Station, and he quotes hosted inference at 1,286 tokens/s on Lithos ($0.15 per million input tokens, $0.60 per million output, cache hits free).
Why It Matters
If the per-task figures hold up on a buyer's own tests, sending every agentic workload to a premium closed model by default becomes hard to justify. The cost levers become routing, caching and the choice of host. Free cache hits help agent loops that resend the same long context most. A local run with full reasoning and tool-call traces strengthens the case for private or sovereign deployment. However, benchmark parity is only with Kimi K3 and GLM 5.3, at about 42 on Humanity's Last Exam and Terminal-Bench, not with the frontier. The evidence is single-run, cherry-picked demos in a CoreWeave-sponsored video, and the pricing is secondhand.
Worth Raising With Customers
- Tiered routing: send high-volume, well-specified agent tasks to an open-weights tier and keep premium closed models for the hardest reasoning. Berman's own PDF-reader build worked this way: Opus 5.5 wrote the spec and the cheap model built it.
- Cost per completed task: before any migration, run the model against the customer's own eval set and compare cost per completed task, not price per token.
- Regulated or sovereign buyers: running open weights on owned hardware is now a credible option for coding agents. The tested setup was a DGX Station, though. Quantized versions on consumer GPUs are untested.