But stressing instances regularly to test them to find a better one is something that you could probably do on your own, but as a service I have serious doubts if the providers would like that from a given scale. I'm not sure, but I don't think that would be something rare to have you account suspended. Perhaps, if you arrive a some type of agreement with them and their "business model" is compatible wit that, maybe. But, don't give me too much credit in this, I'm only speculating.