I’ve thought about setting something like this up for the major clouds & SaaS.

The biggest problem is that I’d have to run some dummy loads on all their services in all regions - even at the lowest tiers I’d probably be looking at a few thousand a month just to keep the service up.

I've considered doing this but I think it would only be feasible as an enterprise offering. The costs of continuously making API calls to start machines, test network performance etc would be quite high.