The wonderful site, http://cloudharmony.com/speedtest/run allows you to run tests on latency, small and large file download speed. Depending on the nature of your application, the choice of a provider is crucial (of course price is another important factor). In the tests, Large File Download category, Amazon S3 is the winner with an average of 15.33 Mb/s. This might be suitable for applications working with large files (pdfs, catalogs, repositories). Windows Azure Service is the winner of the small file category with around 2.5 Mb/s. The difference between the large and small file is significant. This order of magnitude difference is probably due to the overhead of authentication, establishing a connection etc. Once the pipe is secure and ready, you are probably bound to the limitations of your IPO as well as the cloud service provider's SLA. Latency might be a concern for high throughput applications - I would argue that self-hosting or keeping the applications close