I have access to effectively infinite API tokens for all models from Anthropic as well as OpenAI. The differential in performance in complex tasks is vast and strongly in favor of Opus, in my experience. I do not use the official harnesses for either model, though - as they are not my taste.

Codex is closer to my taste, as it is at least a native app and not typescript slop. But the model is just not up to snuff.

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