There's not a whole lot to say about these, they look great and they work. Period. I think they have a little better feel to them than the original caps, but they are slightly larger.
As the title suggests, these things are a vast improvement over the stock knobs/faders that come with even today's expensive DJ gear.
I purchased them primarily to color organize areas of my gear setup and to get a little more "grippiness" from my knobs/faders but quickly realized how invaluable they would be in low light scenarios as well. If you always perform when the sun is out or the lights are on, I guess you don't have to worry about it.
Some colors are awesome in low light/black light (Magenta, Pink, Glow, Neon Green, etc.) and some don't (Grey, Blue, Purple). You decide what is best for your workflow.
Check out my Instagram for photos of my S8 and Chroma Caps.