Valve caps with blinking lights, dice or other stuff may look neat as an impulse idea near the cash register but they are just un-sprung spinning mass and worse, to me.
The job of your valve cap is to form an air tight seal so that no air can escape from your tire even when the valve core is forced to open by centrifugal force. I’ve yet to find a seal inside any of these toy caps.
If you still have rubber valve stems you may be surprised to learn that the weight of a toy cap times the rotating speed of the wheel is more than enough to fold the stem over till the cap is pressed against the rim. Do you really want to be folding the thing that keeps the air in your tires?
On my bikes you will only find a properly tightened metal valve cap with a seal inside. You will also find that I have all the air pressure I started with and no extra spinning mass.