I've just grabbed a new board from Keyboard Co. I'm fortunate to work in a quiet, open-planned office in the Suffolk countryside. I prefer tactile, clicky switches and I knew these wouldn't go down well with my co-workers!
Fitting these o-rings is a piece of cake. It's a little time-consuming, but it dampens the volume of the keypresses as you'd expect and it also refines the feel of the key at the furthest point of it's travel.
Without o-rings I've noticed I tend to bottom-out as I'm quite heavy-handed when I type. This results in a clunky sound and in hindsight left me feeling a little fatigued after a day's work. These red o-rings are apparently softer than the other colorssizes and I feel like they add a ncie level of cushioning and rebound to my key presses. I'd be interested in trying the other varieties, but as a simple, cheap addition to a nice keyboard, these work wonders!