Internal Eval: GPT 6.1 Sol Beats Opus 5.5 at 40% of the Cost

Developer Emil Ahlback's internal knowledge-work evaluation found GPT 6.1 Sol to be the strongest model tested, completing more work independently than Claude Opus 5.5 at 40% of the cost and nearly twice the speed.

2026-09-30 ~ 2026-09-30 · 3 related posts

• Internal evals put GPT 6.1 Sol on top: beats Claude Opus 5.5 at 40% cost, 2x speed — emilahlback · 2026-09-30
• Internal evals: GPT 6.1 Sol beats Claude Opus 5.5 on knowledge work at 40% of the cost — emilahlback · 2026-09-30
• Internal evals: GPT 6.1 Sol beats Claude Opus 5.5 on knowledge work at 40% of the cost — emilahlback · 2026-09-30