Composer 2.5 vs Opus | The Results Are Brutal

Cursor just released Composer 2.5, and it's performing on par with Opus 4.7 across multiple benchmarks while costing a fraction of the price. Trained on Colossus 2 (xAI's 200,000 GPU supercomputer) and built on the open-source Moonshot Kimi K2.5 checkpoint, this is the first time Cursor's in-house model is genuinely competitive with frontier models. In this video, I break down the benchmarks (Terminal Bench, SWE-bench Multilingual, Cursor Bench), the training approach using textual feedback and synthetic data, pricing comparison vs Opus 4.7 and GPT-5.5, and then I run it on a real security audit task for one of my own applications to see how it actually performs. Honest take: Composer 2 has been my go-to for a while, and 2.5 is a noticeable step up. The fast variant is impressive for the speed, and the cheaper slow variant at $0.5/M input is hard to beat for routine work. ⏱️ Chapters 0:00 Introducing Composer 2.5 1:03 Cost per task comparison 1:20 Built on Kimi K2.5 open-source checkpoint 1:29 Training method: textual feedback & hints 1:51 Synthetic data — 25x more tasks than Composer 2 2:15 Pricing breakdown 2:33 How to access Composer 2.5 2:55 Real test: security audit + pull request 3:48 Final thoughts 🔗 Links Cursor: https://cursor.com If you found this useful, drop a comment with what you'd like me to test next on Composer 2.5. #Cursor #Composer25 #AICoding #DeveloperTools #AI We're introducing Composer 2.5 from Cursor, a significant jump in artificial intelligence performance, now on par with Opus 4.7. This breakthrough is largely due to its training on xai colossus, specifically the colossus ii supercomputer. This advancement in ai technology promises a cheaper alternative to other frontier models, shaping the future of ai.