I don't mean to be negative about this particular brand, but I'd suggest that another good source on Beneteau products are boat yards, particularly large ones in areas where Beneteaus sell well. These boats seem to consistently suffer from manufacturing problems - or perhaps it's fairer to say they suffer problems when used regularly/demandingly, tho' in ways Beneteau approves of. Boatyards are great places to discover what happens in such cases.
I'm at a yard at the moment with two excellent examples. The First 375 that's rafted outboard of us at the moment, waiting its turn for a bottom job, looks to be generally in good shape. However, the deck mold is separating from the hull mold back aft, where the transom line is and where the joint is gelcoated over. Not a gelcoat crack, but a separation. Knowing this makes one begin to think about causes...and therefore understand a bit more about the hull torquing/racking in a seaway and perhaps what limits exist for Beneteaus in this regard.
Another example is up on the hard, a 3-yr old Beneteau 57, roughly a 600,000 Euro boat. Fuel tank vents have led to her injection pump being demolished and needing replacement (altho' this was equally due to inadequate pre-filtering of the fuel) and a number of other systems issues. But the big surprise is her ballast keel. In addition to a noticeable gap in the keel/keel stub joint, we're seeing a crack that started at the trailing edge of the keel, slowly working its way horizontally and forward, apparently trying to mate up with the main section of the keel where it mates with the hull. (The mating surfaces are 'stepped' on this keel stub/keel rather than being one straight horizontal line). Beneteau has refused to address this, suggesting the crack be filled with putty. When deciding to 'bolt' the keel sections together and inhibit further crack creep, the vendor who does this work discovered the keel wasn't all lead, but rather a lead casting covered with an aluminum alloy. (What strange arrangement is this?! Well, the keel was made by a subcontractor...and so who knows; Beneteau doesn't). In this case, we learn multiple things: Beneteau's attitude towards warranty claims, subcontracting of keels, and specific defects - none of which we would probably assume when first learning about the boat.
Just like Jeanneau, Catalina, Hunter (Legend in the UK) and Bavaria, Beneteau makes a large number of boats, year in & year out. Many are lightly used; others are used sufficiently to begin surfacing issues like those above. Digging around yards will help identify some of them; networking with other owners who use their boats extensively is another way. Some Beneteaus - moreso the First series - hold up well; some do not.