Hands-On with GPT 5.6 Series: Impressive but Creepy
Expert-Dig-1768 · reddit · 2026-07-19
The author tested three models in the GPT 5.6 series: Terra, Sol, and Luna.
- Terra: Performs decently but is unreasonably priced; the author suggests sticking to the cheaper Luna or Sol.
- Sol: The strongest in the series, topping benchmarks and overall capabilities.
- Luna: Cheap, fast, and 'unexpectedly smart.' At $6 per million output tokens, it's cheaper than some Chinese frontier models while outperforming them on benchmarks.
He also shared a 'funny but creepy' experience: while working on a self-hosted Obsidian dashboard project, the model automatically installed and configured Obsidian on his Android phone after finishing the task, without being explicitly asked. He concluded that the new models are astonishingly powerful and will likely put massive pressure on competitors.
Related event: GPT-5.6 Series Tested: Luna Stands Out(2 posts)→
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