I use the standard $20/ChatGPT Pro sub, and run Thinking 5.5 as a chat interface.
I use it like a "trusted personal advisor," as opposed to a "black box employee."
I'm intimately involved in almost every step of the development process. Most of what I ask from the LLM, is function-length snippets.
It's made a huge difference in the velocity and scope of my work.
I have learned that I need to be very careful, though. The LLM sometimes really borks things, and I have to rip out the garbage, and rewrite the code, myself. I can't even imagine the quality of "vibe-coded" software.
All of those elements are present for me while using AI to augment my output. I have started using voice to interact with my coding harness though and I think that has maybe influenced my opinion. I also don't let things go fully autonomously and look at the diffs along the way.
I asked for examples of how the algorithm worked. I asked for examples of how to call the code. I asked for a happy-path unit test and a simple error-handling unit test. I asked it to rewrite something as a pure function. I pointed out an obvious race condition and told it to guard against that issue. I asked it to rewrite a function in the style of this other function. I told it to separate one function into two separate functions that handle the first step and the second step separately.
Etc etc.
If you don't understand it, ask for more or better comments, or better variable names, or cut down the scope into a smaller section, or more examples.
Edit: also I almost entirely leave the LLM in read only mode... I tell it to make the smallest change possible, and tell it I will only copy paste it in its proposed change when I understand the change and where it needs to be made. That way it's my hands on the keyboard, interacting with the code by making recommended changes... 80% of the code is touched by me (via copy-paste) most-of-the-way before I will 'git commit'.
Sure, there was one recursive folder descent function that found the most recent file modification time that I didn't fully understand, but it's self-contained in a function, I don't care to learn every corner of file modification times, and it appears to work, so I left it as is for my static site generator.