I find that ChatGPT’s Codex reviews - which can also be set up to happen automatically on all PRs - seem smarter than Copilot’s, and make fewer mistakes. But these things change fast, maybe Copilot caught up and I didn’t notice

No codex catches genuine bugs here that multiple reviewers would have overlooked, whilst copilot only comes with nitpicks. And codex does none of those, which is also great.