Allowing equipment to be used while it is undergoing MU is a VERY welcome update. I assume that other players have a preferred hull-turret combination, like I do. I am glad to spend my crystals to upgrade equipment, but I dislike sidelining my favorite equipment while waiting for the MU, or spending crystals to speed up the MU that I would rather spend on a better MU. This is a great, great decision - thanks, developers!