I still use Claude Sonnet 4.5, the free version, not Opus (I don't have access to it for free) for coding and the others, by rotation, depending on what I need. For productive work, a good/suitable AI model justifies the cost of the subscription, but they also become highly addictive so, while I don't like being cut off from working with Claude almost immediately, for the next couple of hours, I think the forced break is useful/needed.