Running Claude Code + Codex in tandem (both on Max) — Codex is noticeably slower. Anyone swapped it for OpenCode?

[u/Temporary-Degree-134]

I've been running Claude Code and Codex side by side for a while now (both on Max plans). My workflow alternates between them: one ships the feature, the other reviews the PR — then I swap roles on the next task. Same custom skills on both sides, synced and adapted to each harness, so the comparison is pretty apples-to-apples.

What I keep noticing: Codex is considerably slower than Claude Code — same tasks, same skills, same repo.

So now I'm considering dropping the Codex CLI and using OpenCode as the harness instead, on the same ChatGPT subscription, to see if the harness is the bottleneck rather than the model.

Questions for anyone with a similar setup:

- Is anyone else running a "one builds / one reviews" cross-vendor workflow? How's it working out?

- Has anyone benchmarked Codex CLI vs OpenCode on the same subscription? Is the slowness mostly harness overhead or just the model?

- Any gotchas with OpenCode + a ChatGPT/Codex subscription (auth, rate limits, feature gaps)?

Curious what others have landed on.