Originally Posted by Brandywine
After the Miami boat show we sort of narrowed our search down to three boats:
Voyage 44 plus or lightly used 50 owner’s version
Broad Blue maybe a 415 or 435 a lightly used 48ish would be ok as well
Besides a large price span, there is a large size span here also. The Manta is really a 38' boat. It is difficult to compare 38'-50' with regard to passage speeds (1-2kt difference in hull length alone), comfort at anchor (they will all be much more comfortable in a rolly anchor, but the larger ones will have more living space, amenities and larger wine lockers and humidors, safety will be more dependent on build and outfitting quality of the boat and the skill level and risk mitigation of the crew, and less dependent on the size of the boat (safety arguments can go both ways regarding vessel size).
As for slamming, I can only speak for our Manta in the conditions that we have sailed it in. We rarely slam in our boat. We do have times when the boat speed, direction and wave conditions are such that water
is rushing through the bridgedeck area and flowing high on the hull sides and bridgedeck. This isn't slamming per se, it's just a constant movement of attached water
flow. I think this trait is a result of the smooth, constant curve surface of the Manta bridgedeck, which has almost no horizontally flat area to it and starts 15' aft of the bows. I'm sure it slows us down, but it doesn't make noise
Most of the hard noise
and vibration comes when in a steep waves just forward of the quarter bow or just aft of the quarter stern. Then the waves miss one bow (or stern) and slam into the other. this happens outside the bridgedeck area, so I don't think height comes into play. It is worse than the same conditions on most monohulls because the hull shape on cats are rather slab sided in these areas.
Motoring directly into a steep chop produces slamming on the bridgedeck when the boat falls onto the waves. In these conditions, I have a difficult time believing any bridgedeck lower than 4-5' would help.
I have sailed other cats in similar conditions that had long horizontal bridgedecks at the same or higher height than our boat that slammed so much your feet hurt.