Salon berths can be the best berth on a boat in bad weather. But they are not suitable for cruising every day. Let me please explain, When you are on a 20 to 26 day passage the last thing you want if you can help it is folks who begin to smell really bad after 3 days in tropical heat sleeping in the salon. Also the salon being a sleeping berth means pillows, sheets, blankets have to be stored somewhere then taken back out every time that person sleeping there is off watch. I know some here are saying that is what sailing is all about but when things are smelly and dirty everyday on a boat one gets tired really easy. On any boat 37 feet and longer there should be good sea berths aft and good exterior storage aft that can be reached from above and not walking through the cabin to get to it.
This is not a big boat for going bluewater and do extensive cruising. I would say that a crew of 2 or 3 is the more adequate to do it.
On this type of relatively small boats the better sea berths were always the saloon berths. They are the ones at the center of the boat and the ones with less sea motion. You are exaggerating regarding the mess. I use a kind of sheet that can involve completely the seat (for protection) and sleep on a personal sheet light bag. Never used the system for more then 10 days but it works perfectly. I know of many guys that use a similar arrangement to cross oceans.
As for making one of the two aft berths into a storage area. I'd rather see it a work room than a storage area. By the way you just can't have both storage and work area, what a mess that is, been there done that. But even if you use the 2nd aft berth as a full time storage area you end up with a mess in no time at all. Seems like every time you want something it is behind 3 sail bags that you have pull out and dump in the salon till you find what you are looking for. That may not sound bad but do it day after day and it gets old. There are better ways than using the 3rd berth as a storage area.
Exterior stowage is great because when open you are looking down at every thing you have in there and should be easier to get at unless you over fill the area with junk. On the 412 I still see no exterior deep lazerettes anywhere in the cockpit or on the stern. Just a 3rd aft berth pushed all the way out to the aft end of the boat. They could have taken 2/3 of a meter off the berth and still had plenty of berth I bet for an ocean going vessel.
But again that is not what HR is looking for anymore they are now looking for a boat to run down to the Med or the Canary's, maybe make the crossing maybe not. Its a safe boat in most ways just not as well designed as other boats.
I guess that there is some confusion here. The Two Cabin HR has not a 3th cabin. It has a big locker that can be accessed from the cockpit and eventually through the interior by the head. The boat has not a working space, unless it is modified to have one since the space is there.
What the 2 cabin boat has it is just a big storage space. that should not come as a surprise because it is a common solution used in many cruisers that offer a big storage space at the cost of the third cabin.
As I have said, I like better the XC 42 but I would not consider the boat badly designed, except in what regards an unpractical three cabin versions. In what regards hull design, rig and as a sailingboat the HR have been improving a lot. You have just to look at those two stability curves to see it, not only in speed but also in safety.
For instance, with the boat knocked out at 90º the RM at 90º on the 412 is 7000kgF*m while on the older 40CC is only making 5500KgF*m.
They are as seaworthy or more than before and are not slow boats anymore and point quite well. I call that quite an improvement