MY #1 reason I NEVER use aluminum rings is the ring screws are threaded into the bottom ring (or other side in cases of vertical) and steel screws into aluminum is not a good idea as the ring itself can strip out,sometimes a lot easier than 1 would expect. Aluminum bases such as weaver bases I don't have a problem with but especially since most people really crank the screws down in fear of them coming loose-I've seen hundreds of aluminum rings with screw holes stripped out. And yes,most references to alloy usually are aluminum UNLESS you're talking about a specific type of steel alloy. A lot of people don't realize that ALL types of steel are actually alloys,but steel alloys,not aluminum alloy.