It would be easy to group Gene Troopers with Cauldron's shovelware crap, but this is actually a much different beast. Shows what they could do with a vision, budget and development time to make it happen; sort of like Chaser but less flawed. They've created strange and interesting alien environments that were visually impressive in 2005 and still look unique and very colorful today, seeing as the game world the exact opposite of "grounded/realistic" or drab. Alien NPCs and practically all the player's weapons are also completely wacky, something you only see in handful of games like Prey 2006. Because it was the mid-2000s, of course there's also a gravity glove and physics puzzles in the game.
The story is okay and provides enough motivation for the main protagonist as well as the player him-/herself, but at the same time Gene Troopers also doesn't take itself too seriously either which does fit the style of the rest of the game. There are even dialogue options with NPCs and your team mates. Depending on your choices, they can alter the outcome of the campaign and give you a different ending. A little bit like Mass Effect in concept if not execution.
The six hour campaign may not be the most refined one, but it will probably be quite memorable. Gene Troopers is also a great time capsule: very first-gen XBOX in its color palette and presentation, and very mid-2000s in its (at the time) fancy new graphics effects and addition of a physics engine.
Notable issues:
[Technical] Using anything but contemporary 4:3 resolutions breaks the options menu and ingame HUD. Of course you can set a custom resolution override with dgVoodoo2 using widescreen but with black borders for the correct aspect ratio.
[Technical] Has feature set autodetect that fails on modern cards. Permanently disables most graphics effects. Use dgVoodoo2 and set it to GeForce FX 5700.
[Technical] Old physics engine = 60 FPS lock required.
[Design] The final level is almost impossible without god mode.