There is one correction though – your statement:

“Lightweight – We can use Spring Integration as a part of our application while ServiceMix and Mule need to be deployed on separate servers.”

is not entirely correct, as far as Mule is concerned (not too sure about ServiceMix). Mule can be downloaded either as a seperate server, or as a single JAR that can be embedded within your application and run within the same JVM.

Additionally, in case of a separate deployment, it’s also possible to run nultiple instances of Mule on the same machine, with tweaks to the listener ports, etc.

Please see: http://www.mulesoft.org/download-mule-esb-community-edition