Verdict
Built from the measurements below
- Accuracy is too close to call: Llama 3.3 70B Instruct scored 42.5% and Llama 4 Scout 41.2% on the same 80 questions, a gap within what chance alone could produce.
- Llama 4 Scout is 1.4× cheaper per question as billed ($0.00037 vs $0.00053), reasoning tokens included.
- Llama 3.3 70B Instruct generates text 2.7× faster: 42 tokens per second against 15.
- Llama 3.3 70B Instruct starts answering sooner: 0.7 s to the first token, against 1.2 s for Llama 4 Scout.
- Llama 4 Scout accepts more context: 1.3M tokens against 131k.
Which should you choose?
Choose Llama 3.3 70B Instruct for faster streaming, a quicker first token and more hosts to choose from on OpenRouter (9 against 2). Choose Llama 4 Scout for the lower cost per correct answer ($0.0009 against $0.0013) and a 1.3M-token context window. The widest subject gap is in humanities & social science: Llama 3.3 70B Instruct answered 9 of 9 correctly, Llama 4 Scout 6 of 9. With so few questions per subject, treat this as a lead to test on your own prompts, not a result.
Accuracy gap +1.3 points (z = 0.16). We call a winner only when z is at least 1.96, the usual 95% threshold. Speed, latency and price need a 10% margin.