Smaller, bomb-proof vision-ports versus large, spacious, yet somewhat vulnerable "windows". I have both. Depends on the probability of attack by large waves and the potential consequences of penetration. Submarines, other than Nemo's NAUTILUS, don't have them. Many multihulls do have them. Classic wooden boats have tiny openable portholes instead of fixed portlights
. Modern big "windows" seem to have proven their worth and benefit on appropriate craft. Dodgers can fold up and be washed away by big waves, I have personally experienced this exciting moment. Water
gets hurled against the structure with the force of a 55 gallon drum of seawater getting catapulted against you. You learn to duck quickly, or you don't get the chance to do it again. But, it's not the "window" that seems to fail, rather, the entire structure collapses.