Similar experience and timeline with codex, but tried it last week and it's gotten much better in the interim. Codex with 5.2 does a good job at catching (numerical) bugs that Opus misses. I've been comparing them and there's not a clear winner, GPT 5.2 misses things Opus finds and vice versa. But claude-code is still a much better experience and continues to just keep getting better but codex is following, just a few months behind.