Underrated is an Understatement...
...but I had to respond to GS poor review of this game and in general the lackluster response to its release. While I will agree with some statements that there are some flawed points with the game (little character development and extremely frustrating level design) there is much more to enjoy over all with this installment of the series.
First off, Mike Patton rocks as Spencer. I enjoyed his banter and "F" bombs during game play. While Spencer's character design at first put me off I came to appreciate it as being a much more appropriate approach to the character as opposed to the original design (as noted with the unlockable feature). When I applied the original character design, it did not seem to fit the voice acting at all, hence I came to understand the change. Throughout the game, Mr. Patton yells, screams and talks $hit to the barrage of enemies and obstacles that present themselves to the player.
Second, the music/soundtrack. Quite entertaining and worthy of a high budget film. The upgrade of the original score to a fully orchestrated theme is well done. It keeps pace with the action as well as supplies a wonderful homage to the original game.
Third, the gameplay. While the beginning stages offer little fodder to dispose of, the latter stages make up for it 10 fold. There were several reviews that complained about the gun play in this game, and I have no idea what they are talking about. It is simple, fun and enjoyable. As for the Bionic Arm and its function toward playing...WOW, just WOW. Extremely simple yet totally engaging. The target reticule is well designed and the color coding used to distinguish what is what works quite well.
Another aspect that is quite well represented is the menu screens and the interface to move through them. This is repeated in the "hacking" parts of the game, however this is another part that is slightly underutilized.
All in all, I hope they consider a sequel regardless of the poor sales as there is a lot the grow upon. And the only way to continue this series is to bring back Mike Patton...the God of Vocal Cords.