GPT 5.1 has been pure magic in VSCode via the Codex plugin. I can't tell any difference with 5.2 yet. I hope the Codex plugin gets feature parity with CC, Cursor, Kilo Code etc soon. That should increase performance a bit more through scaffolding.

I had assumed OpenAI was irrelevant, but 5.1 has been so much better than Gemini.