38 Super, 45 ACP, 9mm

[Gatorade]

So my grandfather has a Rock Island .45 and .38 Super. He is in great health but he is 90. He has a large collection that will be split between myself and my uncle. So these will probably get split up between us. So talk to me just about caliber here. What are the pros and cons of each besides the obvious availability of .45 in stores as opposed to .38 Super. I reload and have a large enough collection myself that this would not be taken to every range trip. Also I don't have a 1911 in any caliber yet.