Most of my calls end with a time out (on their side) after 10 minutes. I get 524 and 502 errors, sometimes 429, and sometimes a mildly amusing 404 Model not found. The only way I can get reasonable responses is to limit my requests to less than 1400 tokens, which is too little in my application.
And on top of that they actually charge me for every request. Yes, including those 524s, 502s and 429s, where I haven't seen a single byte of a response. That's fraudulent. I reported this to support twice, a week later I haven't even heard back.
Their status page happily states that everything is just fine.
From the forums it seems I'm not the only one experiencing these kinds of problems.
I'd argue "GPT Best Practices" should include having working APIs, support that responds, and not charging customers for responses that are never delivered.