I really like the idea of the pro-velocity and decided to buy it. I think it will be a great training aid. I also bought the half bat as that seems like a fantastic training tool too. If I could do it over again. I would buy just the one hander camwood not that i dont like the big one but the pro-velocity is a much better option.I like both half-bat and the cam wood bat. The main reason I think they can be helpful is the feedback is built into the device. You do not need to instruct them every swing if they are doing it correctly.
I did get the double tee with the camwood and it is a very nice tee.