The issue with December buys, especially ones ran elsewhere than Massdrop, is that a lot of people will be saving up for Christmas - one of the downsides of growing up, instead of blowing money after Christmas you save up before it in order to get stuff for loved ones. This has been a problem before, even MD a couple years ago had sets not do well because of it (GMK SNES, most notably).
That said, Slate and Laser are both imminent, right after 9009, Pristine and Eclipse... This is going to be a rough time for GMK buys no matter what.