I have coached baseball and softball for over 20 years, and this is the best infield surface product I have ever used.
It will not wash away or damage the grass edges surrounding the infield. It is extremely low maintenance and handles water better than any product I have used.
We used it for the first time this year at our tournament, and it held up better than any product I have used in the past (including lava rock and crushed brick). I am sold on it and will use it on my fields from now on.