| Keep Cartesia for raw realtime latency | Cartesia | Keep Cartesia when first-audio speed is the core buying reason, then test same-region P50/P90 latency before switching. |
| Switch to ElevenLabs for voice quality and cloning | ElevenLabs | Switch when voice quality, library depth, cloning, and creator tooling outweigh a pure latency test. |
| Switch to OpenAI TTS for OpenAI-native products | OpenAI TTS | Switch when the migration cost is lower because the product already uses OpenAI models, agents, and realtime audio. |
| Switch to Azure for governance | Azure AI Speech | Switch when compliance review, custom voice governance, Microsoft procurement, and regional operations dominate the cost of ownership. |
| Switch to Fish Audio for creator pricing | Fish Audio | Switch when usage-based cost modeling and creator voice cloning need a commercial alternative to Cartesia and ElevenLabs. |
| Switch to Chatterbox for self-hosting | Chatterbox | Switch when the team can absorb model-hosting migration work and wants MIT-licensed local or on-premise control. |