Rudder. I think the rudder on boat boats is exposed. On that I have to give the Tayana/IP's of the world a big plus.
Deck. Catalina cores their decks as I am certain Sabre does too. I am not sure about all the Sabre, but I will tell you that Catalina lays solid glass around all of the openings (Hatches, vents, etc) to prevent any future delamination (water seeping into the balsa). Anywhere and everywhere there is a deck breach, Catalina uses solid glass. I believe the new Sabres use a foam (Airex) core which is probably a superior coring and may again make for a lighter boat.
Hatches. Well, here comes a big positive and negative. I like a boat with a lot of hatches. I sail south and there are times when it does not get out of the 80's at its coldest at night. The 400 is loaded with hatches... much more than the 426. That makes the 400 a very light, airy boat and comfortable down below. The negatives of hatches is obvious. Though I have always wondered how many hatches have really been ripped off of boats and in what conditions?? Still, I like a lot of air.
Dorades. Here is a big plus for the Sabre and IP's, etc. I really, really like dorades. I am very likely going to install some on our 400. Why? Because when you are underway and it is hot (always for us), you are not leaving your hatches open unless it is very calm or you are motoring, or both. We have two hatches we can leave open on our boat and still sail, but we still take water into them periodically. Same with the portlights. So a boat with ventilation while underway is a much more comfortable boat. Even when it is cold, if you can ventilate the boat, you will reduce the moisture down below and make for an all out more comfortable ride. Catalina should incorporate this.
Portlights. I am a much bigger fan of the portlights of the Sabre. I assume they use Bomar? No matter, a SS hatch with screw down dogs is a far better hatch in my opinion and it looks better. Catalina does not do this because of cost. However, those can be changed out and we have had owners do that.
Hull-Deck Joint. Not all Catalinas are made the same. Not sure who knows this, but the C400, C470, and the new 445 all use a Internal Flange Hull-Deck Joint. None of the other Catalinas do. This is an expensive joint. Basically, you have two solid pieces of glass overlap each other and are chemically bonded. Then, they use the toe rail (these boats have aluminum toe rails) that are T-bolted through the flanges every inch or so along with the stanchions. The final product is a deck joint that is very solid (I am told more solid than the hull and deck around it) and is mechanically and chemically connected. I believe the Sabre uses the same hull-deck joint.