I asked multiple coding agents and models to build the same app: Create a single-page web app at index.html that beautifully renders a GitHub user profile and activity comprehensively. Pick the ID in the URL ?id=…, default to ?id=torvalds. … and compared their quality, cost, and speed. My observations: Quality variance is the highest. Some models / agents produce great visuals, some average, some fail completely. Cost and time variance are lower among the successful models. About 2X variance in each. ...