On Friday, May 8, 2015 at 8:25:28 PM UTC-7, Jonathan St. Cloud wrote:
The DG-300 had issues during construction where the Elan team building the gliders, used non-certified construction methods with resulted in weakening of the wing structure. You should look into the history of the wing problems before purchasing a DG300.

A couple of Elan-built DG-300s (broken in unrelated accidents) were found to have a process problem related to the spar layup. Rather than find out if the problem was more pervasive or find an economical way to inspect, the DG factory apparently decided it was cheaper and easier to declare that all Elan and AMS built DG-300s and 303s (sold before the present management took over) had a problem, prohibited aerobatics, reduced the gross weight and Vne. No DG-300/303 has ever had a structural failure related to this issue. As a practical matter, unless one has DG-303 Acro (like I did) and wanted to do aerobatics, it doesn't much affect a 300 or 303 in day to day cross-country, or club class competition use.

By the way, a similar spar-related problem was also discovered with the Czech built Discus Cs and Duo Discus (one of which I was a part owner of at the time). SH went to some lengths to come up with a means of inspecting the affected gliders (involving cutting several holes and borescopes), and fixing those that were affected, at no expense to the owners. I still have a good deal of confidence in the structural integrity of the DG-300 and 303, not so current DG management.