My favorite new GPT is Not Diamond at https://chat.notdiamond.ai
Like Poe, it enables you to try different GPTs (ChatGPT, Claude, Gemini, Perplexity etc.) in the one place, but it does more. Based on what you ask, it chooses the best GPT for your query.
And you can compare the output of different GPTs side by side. And it does image generation, including the new Flux. And it is free.
