A rigorous analysis of Latency, Token Efficiency, and Reasoning depth across 24 enterprise models and 15 voice synthesis engines.
While reasoning scores have plateaued across top-tier models, the battleground in 2026 has shifted entirely to 'Time to First Token' (TTFT) and Voice Latency. For autonomous agents, speed is now the primary driver of customer satisfaction scores (CSAT).
Key Takeaways
| Model Name | Logic Score | Coding Depth | Latency | Input Cost |
|---|---|---|---|---|
Claude 3.5 Sonnet Rank #1 | 98% | 99% | 240ms | $3.00/M |
GPT-4o (Omni) Rank #2 | 96% | 94% | 180ms | $5.00/M |
Llama 3.1 405B Rank #3 | 92% | 88% | 450ms | $0.10/M |
Gemini 1.5 Pro Rank #4 | 94% | 91% | 310ms | $3.50/M |
For AI Voice Agents, naturalness is secondary to responsiveness. Our benchmarks show that human patience expires after 400ms of silence. We currently recommend Retell AI for high-concurrency appointment centers.
We can run head-to-head model tests on your specific business datasets to determine the most cost-efficient stack.