You need to analyze your scenario and then decide. If you need only transformation or alongside with a simple routing you can use some frameworks like smooks, camel etc.
You need to transform and still a lot of system involved where you need those transformed messages then you could use an ESB.
Then comes selecting the ESB product is also based on you application eco system. All products are amazing and each fits the better than the other in their own application eco system.
First you need to know a few things on Camel / Fuse ESB / Service Mix
All the above revolve around the same, each of them are projects where camel integration framework is the coding De fact o
1.Camel -- Integration framework and the De fact o coding way(sophisticated in its own way and much flexible)
2.Service Mix -- Container for deploying the your integration code. (Camel integration code)
3.Fuse ESB -- Enterprise Feather on the hat of Service Mix where it provides a Studio for coding , a list of components and wrappers like clustering and other facilities around service service mix
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I would like you to also consider Mule ESB which could also and it will be a good contender in your list.
Some answers for your questions
1.You can deploy Camel code or the spring integration code into the what so ever container (all in the hands Maven and jar management thing you need to do....)
2.Service mix is a Apache license and is complete open source and if you need some support I suggest you to choose the FUSE ESB which is not part of JBoss family and powered by RedHat
Please follow this link below for more detailed discussion from other stackoverflow.com users
use the below for your analysis
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