The $200 plan lasts me about 6 days with Opus 5.5. The same plan only lasts half a day if I use Fable 5.2 exclusively.
And although Fable 5.2 was able to solve a few "unsolvable" issues, I didn't find it performing much better than Opus 5.5 most of the time. Even had instances where it made mistakes that Opus would've never made.
So in terms of intelligence and cost, Opus 5.5 is already so well balanced, that it should be our go-to 90% of the time, before we even consider touching Fable 5.2.