Highest performance Python framework for API exposure?

[Alec Taylor]

Which Python framework has benchmarked the highest?

I am looking for a solution to initially run on Heroku or OpenShift;
but eventually run on a pure IaaS.

Will expose the interfaces RESTfully as JSON, purposed to act as the
"glue" between the endpoints, databases (incl. caches) and queues.

An additional requirement is support for serving static, downloadable
content efficiently.

Currently looking at Falcon, Bottle and Werkzeug.

Suggestions are greatly appreciated.

Thanks,

Alec Taylor