Why would anyone use a Sonnet model? Yes, 3.5 was good, but after that I never really used one. Then Sonnet 5.5 came out, and I kind of like it. Here's why. It feels like an extension of Opus 5.5, similar quality in many ways, not all, and way cheaper and faster. It's not super clear when to use Sonnet vs Opus. This is how I use it. Use Sonnet for iterative, quick work, especially design, prototyping, and product work. It's also nice for quick background jobs. Run it on low or medium…