Really interesting, I used it today still lots of issues. Maybe my python notebook is not approach is too complicated for Sonnet? Couldn't be able to fix a custom complex seaborn plot. 4o failed too. o3-mini-high managed to do it really well on the other hand.
After an hour and a half assed working result, i put everything into claude and it made it significant better on the first try and i had not a subscription active with claude.