They took everything that made the first two games great, and created a gem.
First off the game looks beautiful. It looks significatly better than its predecessors. The bosses are more varied and interesting, as are the enemies and environments. Even with new takes on classic environments (like the giant faces) are done in a new way to make everything feel new.
The game also sounds significantly better. The sound effects are still repetetive and mediocre, but the music is fantastic. After a slight fall in part 2, this game does it right with nice, catchy and moody music to fit each stage.
The gameplay is as fun as ever too. There are no real improvements to the core gameplay. You still fly around, shoot things, and upgrade your ship with power-ups in whichever way you see fit. The catch this time around is that you are not limited to specific sets of weapons, now you can customize your ship in any way you like with one of each type of power-up. This adds an even higher level of customization which is very very welcome. The bosses this time around are also much more interesting and varied, which means that you will actually have to do a little bit of strategizing for each battle, instead of mindlessly shooting.
The stages are also varied and unique, requiring all sorts of different flying and shooting skills from the player. The only downfall to this game is that it is much much harder than the games before it. You will find many frustrating moments, die plenty of times, and may not even make it through the final sequence (it took me a week). The challenge is definately hardcore, and this could be a plus or a minus depending on how hard you like your games. About 1/4 of the time the challenge is through cheap kills, and the rest of the time it is just a matter of raising your skill. This is actually a pretty good ratio for a game this old so that's not a problem. It is merely a little frustrating when you are trying to beat the game but keep on dying in the same part over and over again.
The game has no real replay value beyond you wanting to come back and play it merely because it is fun. It is a little longer than part 2, but still short like it should be for an arcade game. It is a bit more skill based this time around so you will likely find it a bit more fulfilling to play than the past games. Either way, this is a must-play for shooter fans. Enjoy.
Graphics: 8/10
Sound: 8/10
Gameplay: 8/10
Value: 8/10
OVERALL: 8/10