wow, I love the keycap - I've been looking for a contoured keycap for some time, aluminium is a great material choice, as the main problem with a contoured keycap would be sweating and grime build up in-between, but since aluminium is cold, less of an issue
It would be great to see R4 versions of these, if R4 versions were available I would probably buy 4 to use them as arrows
The reason: Integrated arrows in 60%/75%'s benefit a lot from differentiation
(And for future, different sizes for different spots, yet since manufacturing costs are a concern, I'm guessing this is unlikely)