I own a Valiant 40, have done long passages on a few Valiant 42s (same
hull mold, with modernizations over the 40), and have been on a few Calibre 40 LRCs. Some thoughts:
The Valiant is the better built boat. It's a tank. In a heavy sea you won't hear a squeak or groan from anywhere on the boat, any of the cabinetry. The Calibre is still a well built boat but the fit and finish is not comparable to the 42. This is one reason why Valiants command the prices that they do. That said, 42 prices have taken a substantial hit in the past few years. Whether they now constitute a good value is a matter of subjective opinion.
The canoe stern has a few advantages and a few disadvantages. Advantages are virtually no hull wave slap at
anchor, and extremely good behavior on a deep reach in a following sea. They track *extremely* well, but still with adequate buoyancy. Also, for a solo sailor, you're in a bit of a manageably sized "cocoon" which I find just about perfect. The round stern rail provides a nice backrest for any position you might like.
Disadvantages are significant, and they all come at
anchor. No easy peasy walk through to your
dinghy, no swim platform, and no lazarette. The two
cockpit lockers are cavernous, but behind the
helm there are two 20lb.
propane tank lockers.
As mentioned there are three
interior layouts for the 42. The most desired, in part because there are fewer of them, are the pullman berth variety. Very nice layout. I think most 42s are center entry with queen bunks in the bow. The aft
cabin is small and a bit short on ventilation.
They both back in reverse like pretty much any other fin-keeled boat with a skeg hung
rudder. I.E., they pull to port, and won't back to starboard unless you get way on and throttle back. You learn to use it to your advantage. For example, you can spin the boat clockwise 360 degrees in little more than it's own length. A MaxProp, which I believe was virtually standard on the 42, makes this pretty easy.
The Valiants are super easy to single-hand for a number of reasons. The small
cockpit with whatever lines you want led back to the cockpit is a big part of it. Everything is within reach with a step or two. Second, the flat
deck and flat coachroof provide a very secure
deck experience when you have to go forward. The true
cutter rig on the Valiants gives you a very manageable sailplan with a moderately sized main, high cut yankee, and staysail. The V42 has a taller rig than the 40 but it's still very manageable.
The V42 has NO
wood on deck. All the
hardware is first-rate, and I believe all the stainless, like the stanchions and pulpits are electro passivated. All I know is all the 316 stainless I've added in the past few years to support
solar panels and devices gets much more surface rust I have to deal with.
I think
maintenance for the boats is comparable, although I had the following experience. A few years ago I did a deck
refit, and stripped every last bit of
hardware off the deck. My boat was over 30 years old and there was not a
single case of bedding having failed. I had to pull the whole
interior head panels down and not only was it easy, but it revealed how well the boat is built in areas you can't usually see. They are well known for having access for maintenance "built-in" as a consideration and for the most part my experience supports that.
The 42 is going to be the faster boat by a hair, not because it's 42 (it's not, that's the bowsprit) but because of it's displacement/length. It's also going to point higher, at least when you let out the staysail.
Honestly I don't think you can go wrong with either boat. That said, if you have the opportunity to actually sail on each of them before making your decision that would be a good move.