Sheathed boats

[chris_gee]

I have been looking at heavy semi full keeled boats for offshore cruising. A possibility however are the two or three skinned glassed boats which I don't know too much about.
Apart from being lighter faster and probably more likely to get bounced around, which may not be so good for an older essentially singlehander, I wonder about the comparative strength.
Specifically I think vinyl has less water penetration than polyester but this was probably not used before say about 1982 if then as it was dearer and may be better and gives better adhesion.
However there seems a bit of a contradiction between expandable wood, and glued rigidity. On one boat there were some cracks and openings in the inner layer which the owner said was normal "temperature movement". Are there any things to specifically look for before getting a surveyor?