This is a nice article keep it up. As far as iam concerned, i find Amazon EC2 service better,
"However, it's important for companies to assess how the functionality of an application meets its business objectives before turning to SaaS. By comparing in-house and SaaS-based applications, a company can evaluate the differences in the applications' functionality and costs.
Since SaaS applications are typically accessed remotely using a Web browser, they are typically more accessible, but they generally offer much less scope for customization and may not perform as well as local applications."