(I began this diatribe as I was drinking my first cup of coffee.)
In this year, size, and price range, the top three have been and are Hatteras, Bertram, and Viking, and not in any particular order. Each is a very-good representation of what each company has had to offer in this size range, and there are pluses and minuses in each.
In any head or bow-quartering-sea situation, you'll be the most comfortable in the Bertram, due mostly to its weight and deep-vee bottom configuration. It is, by the way, the only one that is notable for its deep-vee bottom design, the others having bottom configurations that are referred to as modified-vee, but definitely not deep-vee. That having been said, once you reach your offshore destination and throttle back and begin to troll, the deep-vee loses its great advantage and the boat will then begin to rock 'n' roll. This will get old very quickly.
The Hatteras and the Viking will still give you a respectable ride in the head or bow-quartering sea, and in most cases will give you a more stable ride at trolling speeds. You will have lots of spray in the Viking, but you will have lots of spray in any of these boats in a bow-quartering situation in which there is also a stiff breeze.
A note about the engines -- the naturally aspirated 6-71 is one of the finest engines ever designed and produced by Detroit Diesel. Unfortunately, as the HP got higher, the dependability got lower. At 485HP, the 6-71s tend to come apart way more often than the 450HP models, but even then, one must depend upon the mechanical inspection to prove or disprove the extent of any major overhaul.
And speaking of mechanical inspection/engine surveys, in my opinion that you should use only an authorized DDA distributor/sales/repair facility to do your engine survey, and not "Joe's diesel service" (fictitious name), unless, and only unless, you personally know "Joe" and personally know some of his clientele and personally know his reputation. I'm pretty sure that you'll find the 6-71 (turbo-charged) in both the 41' Viking and the 41' Hatteras.
Jonathan made an important point about the longevity of these high-performance diesel engines that I'd like to restate:
quote:
"You can de-tune either of these motors by taking pitch out of the prop without messing with injectors, etc...... You will lose speed but gain longevity."
This is a very good point as the speed that you'll lose (minimal) is more than gained in the longevity that you'll gain.
The 475HP 6V92TA Detroits, in and of themselves, are generally considered to be a good match to the 42' Bertram. Even though there is additional "room" for higher HP as mentioned by Jonathan, the manner in which they have been run is critical as to what you may expect down the road. Obviously, no matter what, a DDA engine survey with oil samples for the fluids is necessary as part of your buying process.
From your comments, each of these boats should meet your overall ride requirement, especially if, as you stated, you generally fish only 10 to 30-miles offshore with an occasional trip out to the Gulfstream. The fact that you are coming out of a 23' Grady will make any one of these seem like the Queen Mary, so you may wish to consider just how much time that you'll actually be spending offshore as opposed to the amount of time that you'll be spending aboard and cruising the ICW. The change in size, going from 23' to 41' or 42' will definitely change the way that you do your boating. And it's a step in the right direction. Have fun and good luck with the process.
(Whew! See what a few of cups of coffee can do?)