I use both. I avoided codex in late 2025 because it was slow as molasses. I tried it again in February and it was on par with Opus speed.

I like codex(gpt-5.4 high) more for its ability to nitpick my PRs and find bugs. I like opus 4.6 much better for anything dealing with visuals, but I feel its rule adherence is inferior and it is not nearly as thorough on code reviews.

I like working and building better with claude, I like fixing bugs better with codex. Also, claude is much better and faster evolving with skills, plugins, new features I find useful, etc. Codex is always a month behind or more.

I did both for a month at higher tiers, $200 Claude Max and $200 ChatGPT Pro. I was always having to conserve my usage with claude, with codex I could just let it run wild with no cares. In the end, I downgraded claude to the $20 plan and use it on occasion, and I have kept the $200 codex sub.

I also have Claude at work, so I'll know pretty soon if I want to swap subs again, but for now, I'm sticking with codex at home.