I think the 50 inch mark would be the minimum. I personally would not have a real mount even if i failed to revive a trophy fish. I would get some good pics, eat it and have a graphite reproduction made for the wall.

Northern and Muskie taste pretty much the same (excellent) as long as you keep them alive until they are filleted and then take the time to remove all of the bones, reddish fatty meat, and anything else that doesn't look like nice firm yellow flesh. We had a TFF northern for dinner last night along with a few panfish. I steamed them on top of a lemongrass coconut yellow curry with the last butternut squash from the root cellar. Mmmm.