Having a hard time deciding which item to have when doing the quest for the shrine of Clavicus Vile? well here it is, all you need to do is first duplicate the Umbra sword keep it in your house or if you have the extra content (Battlehorn castle, Wizards tower, vile lair or the thieves den which ever one you have) once you have done that you can then return on one umbra sword to him and then you will receive Masque of Clavicus Vile and Umbra's Sword.

once you have done you can put in on of the display cases and you can also do the same for the shrine of Hermaeus Mora and duplicate the Oghma Infinium book. You can then easily increase your skills and attributes and any other special rewards from other shrines and put them in the display cases if you would like to. That's what I do instead of use all of them in combat.