Comment by YuechenLi
4 hours ago
Fable is just way too expensive and limited compared to GPT 5.6 Sol, and the only task that requires that level of intelligence is frontier scientific research. I use GPT/Codex primarily for coding and usually keep Claude on Sonnet 5 most of the time as I use Claude primarily to debug/brainstorm/make frontends as a supplement to GPT.
I do not agree. Fable is the only model I can leave unattended and give me results for part of my work which is just devops related tasking.
I can hand hold opus but I would rather just ask fable to do it and give me the result that I review and works. Opus will waste tokens and still require me to help nudge it in the right directions.
I think the next gen models from china will put us in a spot that the cost can plummet and I won’t need the Sota from anthropic
I second the parent comment. 5.6 sol xhigh is not only better than fable I can also run it forever without worrying about limits. The frontend has gotten much better too with the plugins that come with codex.
Agreed. I have the highest individual plan for both. I run out of Fable credits midweek, while I usually have some credit with Chatgpt left despite it having to carry Fables load for the second half of the week.
Also, Sol doesn't refuse constantly and speaks like an engineer rather than a deranged academic.
Opus 5 is legitimately terrible and can't or won't follow instructions. It is of negative utility and does more harm than good to my codebase.
In a frontier scientific research environment, funding is often limited, so personal subscriptions are more common. Fable can hit a 5-hour usage limit on the Max subscription tier before it finishes a single complex math prompt. Most of the time you get one or two if you reduce context and question complexity. Most of my colleagues are cancelling their subscriptions because of that, and just using Sol instead, which is virtually unlimited on the Pro tier.
I thought Sol was on par with Opus, so comparing it to Fable is apples and (very expensive) oranges?
I've used all three extensively.
Most of the benchmarks have exceeded their usefulness. Opus 5 beats fable 5 on many of them. Anyone who has used both models will notice immediately that this doesn't translate to the real world. Opus 5 is nothing short of a regression from Opus 4.8. Fable is genuinely a great model so long as you don't trigger a guard rail and it downgrades.
Sol in my experience isn't significantly different than fable ignoring that Sol burns usage 10x faster but the end result is hard to differentiate.
GLM 5.3 is a hair behind these two.
An anecdote but not an original one from the people I talk to.
Sol routinely catches stuff in review that fable misses for me. It's impossible to compare them meaningfully because it's a complete dice roll - but in practice using both in my projects I can get work done with both, and Opus 5 is far more tedious.
But Fable security false positives and pricing just make it not worth compared to Sol IMO.
Yeah, it's pretty much apples to oranges, and I don't consider GPT and Claude to be interchangeable at all. From my anecdotal experience, GPTs generally codes more creatively and verbosely but Claudes tend to code more carefully and precisely, so the result is that GPTs generally finds more creative solutions to problems but also writes buggier code, which is why I converged on the setup of GPT/Codex for implementation and Claude for debugging, which feels more like a force multiplier than using each model individually.