I've said it before, I'll say it again... IMHO, the single best resource for addressing these criteria is John Rousmaniere's DESIRABLE AND UNDESIRABLE CHARACTERISTICS OF OFFSHORE YACHTS...
Don't take too seriously the comments of those who may opine that there is no such thing as a bluewater boat, or that most any plastic fantastic can be "modified" or "beefed up" for bluewater sailing...
Some boats and designs simply ARE far more suitable than others or most for such sailing, it's completely beyond me why some try so hard to deny this...
I never said any plastic fantastic could be modified. Some are plain and simply designed for coastal work.
Well, this could get into a very heated discussion. My dad owns (and I am part owner) of a Tayana Vancouver 42, which by most would be considered a "bluewater" boat. I have sailed a multitude of other boats. I will escape the Hunter comments because I have not owned one. However, I have not had those issues on a Catalina. I own a Catalin 400, have owned and cruised a Catalina 380 (the old Morgan hull 38 altered with a different top, incidentally), 320, and 250. And to be fair, Hunter has made some mistakes. But they have also made some well made boats. I understand teh 49 is a well made boat, but my knolwedge on that vessel other than the boat show is hearsay.
There are several lines of the Catalinas that are not meant to be offshore boats. They are not designed for that. The larger boats are and I am here to tell you they can and have been there. I have done it. I have the pics here too. I had no problems, at all. Never have. I also put my kids on board one and I guarantee you that I am very cautious about where and what we do as such.
Many of the failures attributed with these boats have less to do witht he boat and more to do with the equipment on board. If it is a hull-deck joint failure, that is the fault of the designer and yard. If the chain plate rips loose, that is a mfg issue or design issue. If the head fails, that is the fault of the head manufacturer. All things inside a sailboat are not manufactured by that sailboat. In fact, most of them are not: from winches, portholes, heads, electronics, batteries, running/standing rigging, etc. Why people fault the manufacturer for failures on those is beyond me. Now, if they were incorrectly installed at the mfg, that is an issue. But when discussing the fasability of a production boat going "offshore" when the vast percentage of the equipment on that boat trasncends to other manufacturers that are considered "bluewater", one needs to stand back and ask how much of this is a design failure and how much is a basic equipment failure that could happen to any manufacturer that uses that product.
The issue with many production boats for long term LA or cruising, in my opinion, is storage, handholds (on some models), and tankage. There are some other things, but that is a good start. I also have an issue with accessibility to systems which is more of a problem with some manufacturers than others, and some models over others.
One of the things I like about Valiants, for example, is that most of the entire boat is built THEN they put in all the plumbing and other systems. They do this to make sure things are accessible and removeable afterwards. It costs more to do that and it is shown in the price. Most production boats do not do that. Everything is assembled in stages to minimize man hours. However, I will tell you that I have yet to find anything on a Catalina that is not removeable. They have done a very good job on that. Incidentally, my boat was about 1000 feet from where tehy laid up the hulls for the Valiants (for many years) so I know the boats fairly well.
Tankage is an issue on production boats. I have seen them start trying to increase their tankage on some of the newer boats. But they are also taking away much of the cabinetry. Reason of course is costs, but I don't like it. Depending on the boat, you can correct the tankage issues. I know you can in the C400 an other larger boats. I also had to custom build cabinetry to increase my storage capacity. This is a real negative of production boats.
ANother thing I do not like about most production boats is their lifelines, which are too short. I strongly prefer the taller (30/36") lifelines versus the knee trippers they put on production boats. I have been in some nasty seas and have never gone over, but I do not like them.
I have no problem with the rigging on either the 380 or the C400. In fact, I have a separate trysail track on my mast which many higher end boats do not have. My chain plates are easily accessible and have never leaked. I have never had a hatch leaak and believe me, they have taken their share of being under a wave. I have had the portlights leak. This is not an uncmomon problem on any boat with portlights. THey simply had to be reset.
My hull to deck joint is a Internal Flange which is only used on the 400, 470 (and maybe the new 445). It does not and has never leaked. I have had no reports of a leaking H-D joint on any 400. I have not been tech editor of the other boats so do not know for sure as well.
I have had no reports of any steering failures on any C400. We had a problem with a sheave alignment on some models, but that was corrected.
Th bilges in the c400 up to HN#309ish are deep on every tack and drain to the middle.
The c400 is a perfomance cruiser like the 445. I did 9.4 coming across the gulf. THe 380 can barely get out of its own way. It is a very heavy, older desgned boat like I find many of the "bluewater" boats. I will never have another boat that does not perform well and meet or exceed hull speed. For example, my dad's Tayana is slower than crap and he is happy with 6 knots. At 6 knots, I am checking to make sure my anchor is still up.
Boats are trade-offs. I have said there is no such thing as a bluewater boat. I stand by that. I do believe there are boats better suited for long distance cruising, but it all comes with tradeoffs. Depending on he boat/manufacturer, you can modify these things to your prefernce and destination. The issue is that on some boats, to modify it for long distance crusiing, the cost to doso will exceed what it takes to just go out and get a boat for long distance cruising. That does not make the long distance cruising boat "better"... only better for that use.
I also believe the vast majority of the success of a vessel offshore stand with its crew and not with the boat. For those that want to argue that their Valiant can wihstand a Cat 5 hurricane offshore longer than my Catalina, I will not argue that point, except to say that I wouldn't be there in the first place. Next someone will say that if you are crossing the Atlantic, you may not get to choose your weather. I agree. But that is not to say that the typical weather encountered would not be survivable by a production boat witht eh right crew.
The point is to know your boat and yourself. Buy the boat for where you want to go and what you want to do. If you are hell bent on doing a circum, I don't think a Catalina is for you. You would probably b better off with a boat built for that purpose. It is not to say that a production boat could not, it is simply that the cost to change many of the things that I personally feel are necessary would be cost prohibitive (though I am personally about there... ugh). But buying a Valiant to go sit in the Keys or Bahmas I think is equally a bad decision, and maybe worse.
These are my opinions. I know Catalinas pretty well and am very happy with teh right boat for long distance cruising. I cannot comment on the Hunters as I have not owned one... but they are a completely different manufacturer and I do not think it is fair to group them together.