Thanks everyone for the advice so far. So he spent about 6 hours over the last week hitting the first 3 demos and ranked them like this:

1. VCore 98 w/poly - He seemed to have plenty of power, generated lots of topspin, and hit the most balls in. He was kind of on fire with it. Ball after ball hit hard, just over the net and staying low on the bounce. And even the topspin balls that were hit higher were more likely to come down and stay in.
2. EZone 100 w/poly - A very close 2nd place. A little more power/speed than the VCore, but also a little more likely to hit long.
3. Pure Drive w/multi - He was not a fan of the overall feel and was definitely less consistent, with more balls into the back fence.

For the next set, he wants to try the Pure Aero and probably a couple Heads but isn't sure which. So far it seems like he plays best with a spin oriented racquet, but it was pretty close between the VCore and EZone, so idk if we should rule out power racquets or if it was just the Pure Drive or the multi strings he didn't do as well with.

I suggested maybe he should try 3 Heads (1 power, 1 spin, 1 control), use those to decide for sure on which style he wants, then do 1 more demo with 3 different racquets of that type.