So I guess that based on what I've read here the compromise is to go to 12 inches and see how well the model trims out. I suppose for most of these Classics the gear length would be able to handle a 12 inch prop with minimal changes. I bet what Dean was saying about the big props with big pitch would be fine and work well on the bigger, later ships, like EU-1A. It's a massive brute with big surfaces.