I know many pro orgs are using it. It is out of my price range by a lot but I have discussed it with a few pro ball hitting coordinators and they think is the real deal.
The concept is definitely good to capture the right kinetic sequence. Similar systems have been used since the 1980s in track and field albeit it was more clunky and expensive back then. Having the correct sequence is definitely very important, the question is of course how accurate it measures but guys like ochart wouldn't use it if it gave bad data.
I don't think it is cost effective for a single player though, maybe you find a facility that has it. Don't need to use it every day, just use it to check occasionally.
I think for a pro org, D1 school or a big facility it probably is a good investment but with an experienced eye you can see a lot about sequence already. I once shot a DM to a pro hitting coordinator that he needs to Kvest his lead arm and he replied with a wink that he did that a lot of times (not always easy to fix).
But data of course is more accurate if you want to use it at a really high level so for pro I would definitely buy it.