JXcore seems to be improved Node.js. Check this carefully designed quote:
JXcore comes with a built-in multithreading support that can be enabled on your existing Node.js applications without additional changes... JXcore multithreading may bring aproximately 30 to 50 percent solid performance advantage over Node.JS cluster module. From http://jxcore.com/
I already tried to install it and it does really work. That's all I can say for now, measuring performance and up-time is tricky and elaborative.
So are there real advantages to switch to JXcore and how to make a decision?
IMHO, JXcore is beneficial for below use cases;
1 - JXcore works on mobile phones (iOS, Android..)
2 - It can be embedded by a Java, Objective-C, C, C++ app.
4 - Packaging and compiling. (https://github.com/jxcore/jxcore/blob/master/doc/HOW_TO_COMPILE.md)
5 - Some of the most popular native modules come built-in with mt support, so you don't bother installing them on a target machine.
6 - Built-in external memory store and sqlite database server. (This one is a life saver on Windows)
I had a problem also. For example, I needed to disable HTTP header byte size check in order make my application running. For some reason they've added extra security checks by default so you may need to update your application a bit.
JXcore is now an open source project with MIT license.