After cramping miserably 60k into the 2019 Vietnam Half Ironman and losing the race because of that on the run, I paid a lot more attention to my salt intake during racing and training. It was obvious that the Precision Hydration guys had the option available. I use a mix of the 1500 and 1000 packets in my bottles in most training rides and runs (to get my stomach used to it) and obviously in racing.
Since then, I won my last 2 half ironman events and most running races I have entered. Knowing I will not be cramping or losing all the sodium my muscles need goes a long way to achieve this!