Best all-rounder — the safest choice if you only pay for one assistant
ChatGPT is the broadest assistant available and the sensible default for anyone buying exactly one. Its advantage is not any single capability but the absence of gaps: web search, file analysis, images, voice, code execution and custom agents all work well enough that you rarely need a second tool.
Best for long-document analysis and writing that has to sound human
Claude is the assistant our testers reached for when the input was long or the output had to read well. Its large context window and comparatively restrained prose are the differentiators; image generation and consumer polish are where it trails.
Best for Microsoft 365 companies that live in Excel and Teams
Copilot is the Microsoft 365 answer to Gemini: an assistant embedded in the Office apps with access to your organisation's files and messages. Excel and Teams are where it earns its price; the standalone chat experience is the least impressive of the five.
