Something to realize is that different models require different prompting styles. You can't prompt non-gpt4 models with GPT4 tuned stylistic ticks and expect similar results.

I've gotten great performance from llama2 derivatives. Out of the box performance is not near GPT4 but it is still very strong in its own right. And, if you are able to break down your problem so precise logit control coupled with guidance from forward or backwards chaining on knowledge graphs is applicable, you can easily exceed gpt4's reasoning ability for your domain. No fine-tuning necessary either.

I've been getting useful things out of LLMs since the days of roberta and raw T5, when Large stood for hundreds of millions of parameters. I am flabbergasted when people say a 7B parameter model is no good for them.