Vehicle physics/dynamics in my case and yes, same. I got a lot of mileage out of letting it use Opus/Sonnet sub agents for much of the exploratory and implementation work, which cuts down on token use. I got into way fewer "oh, that's nonsense? what about this then?" loops with Fable and it was the first model that actually tried to reason about the full system rather than fixating on details and chasing bits and pieces out of context. Haven't tried Sol yet but so far haven't had a reason to switch.