> only 7 new have sold in the past 6 months on Bricklink and 0 since November
Yeah, on Bricklink. Have you tried looking at more mainstream places like Ebay? There are dozens of sealed sets selling there.
>a 300% return that is not impressive
Really? You dont think 300% ROI is not impressive? Most of the regular sets from the 1-4th generation also sell at that kind of inflated price so its really not that unusual.