Joe, its probably not the size, but rather the slot setup.....I didn't think the GE would fit, or work, but it did....
wondering if the hubs would interchange.....I don't have a full GE machine to check on something like that.....but was always a curiosity of mine....
personally I think the vanes of the SQ could be a bit larger, they work great for small to medium loads, but on the super size ones, could use a little more kick....