A member of our club bought one of the Passage 450s in California and enlisted the help of a very experienced couple (circumnavigation, multiple trans pacific voyages) to deliver it up the coast.
The first serious wind they encountered, the delivery skipper turned around and refused to continue due to the arch flexing excessively (to his mind) under the loads and sea conditions...
Could have just been that model, or that particular boat, but sounds like it's something to think about.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)