Since I have access to the thinking tokens I can see where it's going wrong and do prompt surgery. But left to it's own devices it gets thing _stupendously_ wrong about 20% of the time with a huge context blowout. So much so that seeing that happen now tells me I've fundamentally asked the wrong question.

Sonnet doesn't suffer from that and solves the task, but doesn't give you much if any, help in how to recover from doing the wrong task.

I'd say that for work work Sonnet 3.5 is still the best, for exploratory work with a human in the loop r1 is better.

Or as someone posted here a few days ago: R1 as the architect, Sonnet3.5 as the worker and critic.