GPT-5.6 Sol became my go-to model in Codex for the hardest work on Flux Visuals, my Minecraft Fabric mod.
Why did I switch to GPT-5.6 Sol? Before that, I tried almost everything from DeepSeek to Claude. But it was Codex that eventually became my main tool for developing Flux Visuals.
I used to work with GPT-5.5, and after the release of 5.6 Sol, the project began to move noticeably faster - it felt almost twice. Sol understands the code base good, fixes errors, works with architecture, Mixins and shaders and more often brings the task to the end without five rounds of alterations.
For me, this was the main reason for switching to Sol.