SP does not do PBT Doubleshot except for DCS top row keys, such as novelty keys, so they don't do full sets in PBT Doubleshot. Vortex uses a different manufacturing process I am guessing that allows them to do full sets, obviously this isn't the forum to discuss that though.
I think this set looks fantastic, its a shame I cant afford to join any keycap group buys for awhile. good luck!