I looked into this topic awhile ago and I believe IIRC that they started the transition from standard marine grad plywood over to Greenwood XL in the 1997 models. It's supposed to resist rot, although I've seen people on here as well as other sites that have had 1997 and newer boats where they've had to replace parts of, or the entire transom. I've even heard of some guys with early 2000's boats that have had issues but it's generally always very confusing or not black and white as to what caused the issues and/or if it was a lack of care on their end, lack of maintenance or so forth. I've seen some claim that their boat had a factory defect that caused the issue, of which I'm sure that is always a possibility, but I don't think it's the case when everyone is claiming that every single time and like they're completely innocent in the matter. I bought my 2004 GW 228 Seafarer last October and she was/is very solid with no soft spots or moisture in the hull or anything like that. I think the biggest part of owning any boat, as well as anything else, is how well it was treated before you boat it or if it was neglected quite badly. If someone stores their boat in an indoor garage or facility, is consistently taking care of it and doing all of the required maintenance then it's going to last a lot longer than someone who leaves their boat in the water year round and doesn't do any sort of maintenance or upkeep. I believe that around 2015, or so? was the year that GW switched over to using no wood at all in the structural parts of their boats.