REST on GAE, what implementation to use?(RESTlet, jersey, other....)

Have somebody experience with using REST on GAE? Maybe you can advise some lightweight REST implementation for this. I found that RESTlet said that they have GAE optimised implementation. RESTlet-GAE Anybody 开发者_运维问答try this?

I am currently using GAE plus Restlet 2.0M6 for a Goolge Apps Domain specific business project and find it very useful. Integration with google Accounts and Data Api is easily done for obvious reasons. However I could not get the XStream lib that is bundled with Restlet to work properly, so I use the very intuitive Simple framework instead for object serialization. Another disadvantage of Restlet is its lack of JSP integration, which is unfortunate if you do not want to use more heavy-weight templating approaches. So far I have used XSLTransformations to render browsable html representations, but am not fully satisfied with it yet and always looking for suggestions.

Update

I am now using Saxon to transform xml on the server. This is a good tutorial on how to use it with App Engine. It is in Jython but not too hard to convert.

Update2

When the xslt approach is too heavy, I take a different approach with the helper package from the Lift framework to enable enriched xhtml templating/binding. This method is based on Scala however.