The spark plug side of the chamber is decent, but the other side looks like it leaves a little to be desired from a pressure recovery standpoint.
That's not the fault of the cnc job though...... The chambers are cast pretty much just like that.

The 2012 version is listed as 285cc and flows 360+, the 2018 version is listed as 325cc, but is really only 301cc...... And flows 330.
I wonder if that's considered "new and improved"?

I can't imagine you could use a flow tube/pipe big enough to get that ex port to flow 299.