Aside from some problems here and there, this game is pretty good for a budget Trek title.
The game is pretty fast-paced arcade action and consists mostly of pointing your weapon arc towards the enemy and firing your phasers until he is blown up. And you continue to do this for wave after wave of enemy ships. There are a couple different mission types besides the basic shoot-em-up ones. There are a couple missions where you will have to use your weopon/sensor arc to scan for a ship's warp trail to follow it around the map, some escort missions, and some station/base defense missions, as well as two or three "warp conduit" missions (which are difficult, but are a lot of fun). So there is enough variation to keep you interested for the 25 or so missions that are available. The earliest missions (set in the Star Trek Enterprise time period) even give your ship weapon blind spots on the right and left sides (oh, sorry, that's "port" and "starboard"), which adds a nice bit of challenge and tactics. Unfortunately, by the time you get to the Original Series missions, this limitation is gone. Too bad.
At the half-way point, however, your ships become so fast and large that they are difficult to manuever, and your targeting cone never gets bigger, so the higher speeds make it even more difficult to target enemy ships. The introduction of some rather tight time limits later in the game leads to some frustrating "if I only had 5 more seconds!" situations which almost ruin the game completely.
Multiplayer is pretty limited and difficult due to the small split-screen format that makes it difficult to know what you're doing at any given time, but it can provide some mild entertainment (especially when you blow up your friend's Romulan warbird with a significantly weaker Klingon Bird of Prey.
Graphics are solid, and there are some nice lighting effects. Some of the special effects (such as the cloaking device) look pretty bland, though. Music tracks fit well into the Star Trek style, but are pretty uninteresting. Voiceovers by William Shatner are nothing to get excited about, but the sound effects are pretty spot-on, really immersing the player into the Trek universe.
This game blows its PS2 Trek predecessors out of the water in terms of gameplay and quality, and its 15-20 dollar price tag means you wont have to break the bank for it. Its pretty short and simple, but still worth the investment if your a PS2-owning Trekkie/Trekker. After all, I'm a pretty die-hard fan, and I thought the game was pretty cool.