APIs win more often than the spreadsheet suggests.
You pay only when tokens flow, absorb bursts without idle replicas, and get mature reliability. Self-host when traffic is steady, model control or data locality matters, and your team can own the serving stack.
- Size GPUs for peak RPS and latency—not daily averages.
- Keep at least two replicas for production availability.
- Benchmark p95 TTFT and inter-token latency at target load.