We tried GPT-5 for a RAG use case, and found that it performs worse than 4.1. We reverted and didn't look back.
Ya, the original commenter likely does not work in the space - hence the ask.
> the evaluation of new models is actually very quantitative.
While you may be able to derive a % correct (and hence quantitative), they are by their nature very much not quantitative. Q&As on written subjects are very much subjective. Example benchmark: https://llm-stats.com/benchmarks/gpqa Even though there are techniques to reduce overfitting, it still isn't eliminated. So it's very much subjective.