Hi emersonrsantos,
Good question!
With Usage, every enterprise customer gets their own fine-tuned model. AWS compute optimizer throws the same standardized model to all of their users. I can't compare our models to the ones AWS compute optimizer uses - but I can tell you that we've never had a complaint about a customer taking a recommendation and regretting it later on.
Additionally, we have humans look over every recommendation to ensure quality. Typically we have an understanding of a customer's cloud infrastructure before they sign up for Usage - and the human in the loop uses that information to grade recommendations produced by Usage's models.