This is crazy, what is the point of all these equivalent models?
Those are just 3 particular technical benchmarks. Presumably Opus is a larger model and has greater world knowledge.
Price going down on each release
Yup. Recursive self improvement presented in hard numbers.
It's long overdue. Sonnet 5 was terrible API value for agentic coding, there were open models like GLM-5.3 Flash that blew it out of the water at 1/20th of the price.
OpenAI and Anthropic's lead is vanishingly small at this point.
> OpenAI and Anthropic's lead is vanishingly small at this point.
Yep, with them nerfing their plans (and apparently planning to release a $500/$600/mo plan) their only advantage is Astra without 5hr limits and with not-too-stringent "cyber" safeguards.
Ergo, it's pretty damn good at unattended RE with the IDA MCP plugin while using most of the weekly quota at $100/mo... and that's it.
Re:Sonnet 5.5
by SubiculumCode on Monday September 28, 2026 @02:10PM
(#49882023)
Yeah, I did kind of feel like the step down from Opus 5.5 was so large as to never make it appealing.
Terminal-Bench: 70.6 (Sonnet 5.5) vs. 66.4% (Opus 5.5)
FrontierCode: 52.1% (Sonnet 5.5 xHigh) vs. 54.4 (Opus 5.5)
CursorBench: 55.5% (Sonnet 5.5) vs. 57.8 (Opus 5.5)
Opus 5.5 might be the best model I've ever used and Sonnet 5.5 matches it and exceeds in some benchmarks. Clearly Anthropic have had some sort of breakthrough with not just performance but also cost with the 5.5 family