It looks like a cool research project. But realistically I would be surprised if it could beat OpenJDK in any benchmark (though I don't think that's the purpose

It looks like a cool research project. But realistically I would be surprised if it could beat OpenJDK in any benchmark (though I don't think that's the purpose of the project). Writing something which is compatible with a specification is one thing, making it performant is another thing. For example it's not that hard to create a webserver from scratch but making it performant takes quite some effort.