Not sure really, seems to have better pick up, but could be illusory.Any significant gains from just removing spark arrestor? My line of thinking is if something goes wrong, pop the screen back in and you're probably still under warranty, just don't tell them.
That warranty is one of the biggest attractions of Echo saws to me.
My dealer suggested taking the gauze out (after I had already done it) he fixed a little electrical fault on the warranty afterwards.
If you went full medieval with the exhaust I suspect you’d invalidate it.