Upgrading them would be dumb. Some may find it cool but I want to find legendary blades like excalibur and ragnorok, and also some awesome spears like gungnir and holy lance. I don't want Curtana and Gae bolg the rest of my days. As cool as they look I would get super bored with the same weapon model for the rest of the game, doesn't matter how many particles they put around it.