I've owned both. The owned, past tense, only applies to Star Trek, sold it. Still have Metallica. Star Trek was a Premium, Metallica is an LE. Can't speak to the Pros specifically.

Star Trek is a smooth game, fun, and also imo very quickly loses its charm. The modes all feel the same, all that changes is the color of the light you're shooting for. The strategy all comes in order of approach things, and some people enjoy that. I personally didn't care when no matter what order you did it felt like playing the same thing. Shoot the red light mode. Shoot the blue light mode.

Metallica is a far more interesting game, to shoot, and to play. Lot more to do that feels unique. Just got another really solid code update recently, it feels finished and polished. It's not a perfect game (what is?) there's some grind feel to it, but I think the latest code reduced that a lot.

IMO Metallica is one of Stern's best games ever, and Star Trek is one of their decent but ultimately forgettable games. Good, but not special. Metallica has the right sparks to be special.