There was a member here named Barbarian who put 90 lbs of metal weights on a single glass detolf shelf for about a month and the shelf held that weight with no problems (he even posted pics). Those glass shelves can support a lot more weight than advertised. Also, with PFs being so big, most collectors have to remove shelves to fit them in a case. Obviously, the best thing to do with the extra shelf is to double it up under a statue. That'll give it extra support. That all said, I only use detolfs for my 1/6 collection. I find the cases to be a little cramped for 1/4 pieces and since the shelves aren't adjustable, it leads to wasted space IMO.