If you write content with AI, model choice matters more than most prompt tweaks. The three major families — Google Gemini, OpenAI GPT, and Anthropic Claude — each have distinct strengths for long-form SEO writing, and the “best” one depends on your niche, language, budget, and volume. This comparison is based on generating thousands of articles across all three (plus the OpenRouter long tail), and ends with concrete recommendations per use case.