Very elegant game, both aesthetically and gameplay wise! It surely remembers me of good, old arcades. I've particularly enjoyed the fluidity of the dice movement: being this a game about reactions I think it was very important to make feel right and you nailed it. I tried other similar games that were much more fiddly or kinda laggy, while this is much more enjoyable.
Two minor notes of other things I've appreciated:
1) the fact that when you make an error, the time slows down (at least I think it does haha!)
2) the small hints you added. A simple thing, yes, but the "sum of opposite sides = 7" really helped me and was crucial when dice pips were not visible.