LA rods are either big (340-3604bbl) or small (273/318) not much difference anywhere else. Bushed or press, that was just a final machine step. I always prefer floaters, just easier to work with. Magnum rods have a narrower wrist pin end.
What do you mean by big or small? The only difference that I know of is that either they have pressed wrist pins or floating. 360 rods will work on a 318 with no problem