I just tried this out, and was VERY impressed with the speed of the plan mode. I was also totally fine with the code it wrote.
Then I made the mistake of saying "run npm run build and fix all issues" (something I've run probably 50 times across codex and cc in the past 2 months). CC does it pretty much 100% of the time. I walked away from Codex, and when I came back, it had installed 2 new node packages, and gone down some crazy rabbit hole with eslint and something else. (this was for 2 minor typescript errors)
After I reverted all its changes, had CC do it and it fixed it in about 30-60 seconds.
Sorry I mis-worded that. It was my BRAIN being in plan mode (I know CC has a plan mode).
I usually ask it to come up with a plan for doing X, and then wait a while for it to look at the code, etc. But in some odd way, GPT-5.1-Codex-Max came up with a plan within 5 seconds. I just found that surprising.
Then I made the mistake of saying "run npm run build and fix all issues" (something I've run probably 50 times across codex and cc in the past 2 months). CC does it pretty much 100% of the time. I walked away from Codex, and when I came back, it had installed 2 new node packages, and gone down some crazy rabbit hole with eslint and something else. (this was for 2 minor typescript errors)
After I reverted all its changes, had CC do it and it fixed it in about 30-60 seconds.
I'll try a few more times. Let's see.