I asked the same question about six or eight months ago. I use my Lee 45 Colt dies for my 454 Cassul. You'll find that you will need to adjust them every time you change from caliber to caliber. Some guys here have a trick, where you insert a washer under the die, which helps make the correction for length quick but to be honest, I wish I had a second set of dies.
Keep in mind, I use Lee dies. I had heard that some 45 Colt dies of other manufactures are short and will not accommodate the longer 454 brass. I don't know what brands do or don't but my Lee dies do.