Text models
Fable 5.2 vs. Gemini 4 Carbon for project work
Compare quality and total cost on the same long-running assignment.
Use the same project tasks
Give each model a code change, a review, and a longer task with a checkpoint. Preserve the same inputs, allowed tools, and success criteria.
Measure actual usage
Compare quotes and recorded charges separately. Include elapsed time, failed attempts, and human correction.
Choose per workload
Prefer the model that meets the acceptance criteria for that workload at a lower total cost.