Well my take is that Zodiac is doing much better now than when they first transitioned to PVC. That isn't really saying all that much. Still, my buddy's 15.5 (and another friends lightly used 17 or so) seems to be holding together pretty well after 5 years of rough and tumble, so they have at least gotten the seams down. Don't know about a 10 year old boat though.
As far as the motor, well, I think I had one of those. Carbed 4-stroke? When in tune it runs quite well. It's heavy for a 40, though, and halfway through the maintenance interval, it can become a pretty cold-blooded beast as far as starting goes (which is why I was glad to have electric start.) Other than that, it seemed to run great, if a bit underpowered for its rating.
So, I guess you've got to ask yourself if you really need another project boat?
Luck whichever way you go;