We use Scorekeeper and Turbostats. I doubt there is a better product out there. That having been said, there are some glitches (from prior posts, looks like we need to get updates to deal with the flex situation; do the updates also address courtesy runners?). And you need to be really careful about simply accepting the Scorekeeper calculation of earned runs. Frankly, I would never rely solely on the palm as a book. Batteries running out can be a nightmare and we've also had problems with: 1) getting behind because of crazy plays that are difficult to score on the palm and 2) "fatal errors" that shut the program down.
I'd also like to hear from anyone who has been able to use the pitch location function. It seems too much to ask the person keeping the palm to score the game AND the pitch locations, but I can't figure out how an additional person could track only the pitch type/locations. Fortunately, it is very easy for the person keeping the palm to record strikes and balls, which is invaluable if you are interested in the pitch count for your pitcher.
Despite the problems, we love the program. When Scorekeeper fails in any given game, we simply manually enter the stats in Turbostats from the written book.