From a former Stadia user; latency was never an issue or noticeable with a 4K stream. And I've played quite a bit of fast paced shooters in the platform.
The experience is extremely dependent on location, bandwidth, local setup and availability of close services (in my case, the closest DC was <15ms away according to Stadia telemetry).
The experience is extremely dependent on location, bandwidth, local setup and availability of close services (in my case, the closest DC was <15ms away according to Stadia telemetry).