We tested the paid versions of ChatGPT 5, Gemini 2.5, Grok 4, and DeepSeek across nine real-world categories -- including problem-solving, image and video generation, fact-checking, analysis, creativity, and deep research. We paid for every tool tested -- no free tiers, no shortcuts. This is an independent comparison based purely on real performance, not hype. Which AI is truly the smartest? Which AI is Best? | 24:18 Versus | 447K subscribers | 407,247 views | October 22, 2025 0:00 Intro 0:30 Problem solving 2:47 Image generation 5:08 Fact checking 7:36 Analysis 11:00 Video generation 14:20 Generation 16:03 Voice mode 19:34...