Such a good question, I have tried them all, and they all have their pro and cons. We have been fine-tuning and using RAG to create better models for different purposes. They perform better than generic GPTs
Alternatives there are tons.. but better ones? Well, that depends on what you need it for, what you'd like to achieve.
Coding? Creative writing? Simple comment posts? Brainstorming? Are you looking for an open source one? etc.
Not to mention, that there might be the case where you'd say "yeah, gpt is better but, this one also does the job and a lot cheaper".. :)
So all in all: depends on the usecase.
Some examples:
Gemini, Mistral, Claude, Llama etc.
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