Looks like I messed up! I don't have the GSL and GTD chips on me, but I have them on order from SP.
Today, a magical package arrived: the SoWaRe color samples.
I tried my best to color match the chips before I sent them to GMK, and got Pantone 424 and 428. Here is my synopsis based on first look with the pantones (granted, my eye may just be bad at the color matching).
The light grey is close, but the dark grey is pretty off. I know other sets that had issues matching colors, but this might just be a thing with the different surfaces of the glossy pantone book, and the ABS surface, and how light refracts off of it.
I'll repost photos when I get the SP color ships.
Left: TU2 with SoWaRe Light Grey (GSL)
Right: Hydro

Left: TU2 with SoWaRe Dark Grey (GTD)
Right: Hyperfuse R2
