Source: Consulted for a few companies to help them finetune a bunch of LLMs. Typical categorical / data extraction use cases would have ~10x fewer errors at 100x lower inference cost than using the OpenAI models at the time.
I did an experiment where I did very simple SFT on Mistral 7b and it was extremely good at converting receipt images into structured json outputs and I only used 1,000 examples. The difficulty is trying to get a diverse enough set of examples, evaling, etc.
If you have great data with simple input output pairs, you should really give it a shot.
like this | Model | DocType% | Year% | Subject% | In $/MTok |
|----------------|----|-----|----|-------|
| llama-70b -----| 83 | 98 | 96 | $0.72 |
| gpt-oss-20b ---| 83 | 97 | 92 | $0.07 |
| ministral-14b -| 84 | 100 | 90 | $0.20 |
| gemma-4b ------| 75 | 93 | 91 | $0.04 |
| glm-flash-30b -| 83 | 93 | 90 | $0.07 |
| llama-1b ------| 47 | 90 | 58 | $0.10 |