N=2 anecdata but just this week we were discussing setting up a couple of seats with OpenAI as a trial for switching. There are other advantages too, such as being able to bring your own harness including Ai-integrated editors / ACP clients such as Jetbrains, VS Code, and Zed. I think OpenAI and Altman are a clear step more evil than Anthropic and Amodei so I really hate to say it, but with the degradation in model output interpretability, all of the cleverness and power of the Claude Code harness hasn't been enough to offset a genuine falloff in productivity for anything other than total hands-off automation.

That said, the duo of Opus 5 and Sonnet 5 do a fantastic job at fully automated work, and Claude Code still stands head and shoulders above the rest.