When do you choose a Conversion Service instead of a Transformer

[kxen]

When is it better to use a Conversion Service rather than a Transformer? Would it be an abuse of the Conversion Service to use them like Transformers and just forget Transformers all together?

I ask because I have a service that expects a result, and for a normal flow or a soap fault I have transformers to transform the response into the desired type.
For other exceptions I'm considering options on how to handle this, and I noticed the this line for the log:

2012-08-22 10:02:04,782 [main] DEBUG org.springframework.integration.gateway.GatewayProxyFactoryBean - Unable to attempt conversion of Message payload types. Component 'cardActivationService' has no explicit ConversionService reference, and there is no 'integrationConversionService' bean within the context.

This has me thinking that I could use a Conversion Service to take MessageHandlingExceptions and return the desired type.


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05-NOV-2012
After working with this more I can see that two have nothing to do with each other, and that you can't have a CoversionService do the job of a transformer. Now my question is, when should I use a ConversionService?