The big advantage of GN is that it is generally directed at a known stock of adults in a situation where it should be possible to have an accurate idea of the run size.

The biggest disadvantage is that it is obvious and in your face. Also, while it is extremely size selective it will take anything of that size. I have seen mesh size restrictions used very efficiently to protect one species while harvesting another.

The method(s) that are the least supportable biologically and energetically (energy used to catch them) are the marine mixed stock fisheries.