I use the Local harness in vs code with a GitHub copilot max plan. Gives access to the best models from OpenAI and Anthropic (I use 6.1 sol, Astra, and opus 5.5 for most things). The Local harness has granular keep/undo and nice interface in general for reviewing changes, which is important for mission critical code. Unfortunately the copilot team is trying to force the less capable, more YOLO-mode "copilot" harness on people going forward. The community is somewhat getting them to walk that back but they seem to be missing the mark on what differentiates their product until people complain.

I also use chatgpt desktop for some tasks through a chatgpt teams/business plan. I briefly tried to set up codex cloud and it was a mess, not following startup instructions so I gave up.