Absolutely, having P99 of sub-ms is of course way more attractive than 25ms - with a SaaS offering you always have the network latency to the provider in the path, which is why multi region capabilities are so important for this case. But you’ll never beat systems where the decision can be made locally.

Have you any documentation on your approach publicly available? I‘d love to get some education and insights from other large scale authz systems! We have a couple of ideas such as running a local replica in our customer’s stack but nothing concrete yet.