The red release button is easy on the cable release thread my X100 bolts, falls at the already eye-catching camera immediately catches the eye and prevents camera shake in some situations, because of the original button but offers something a little contact surface for the finger.
Thus, while not necessarily required purchase, but still a buy, I do not regret.
Some reviewers complain that the delivered red is not quite as bright as on the product photos. I like it but still and it evaluates the overall picture of the corresponding camera on!
It is a pity only that you only have a choice on Amazon. The button is available according to the description both in 3 colors (black, red and silver) as well as concave and convex shape.
At Amazon, there is (for some, unfortunately) only one alternative: red and concave, which would anyway have been the first choice for me ...