I can't really imagine this game taking 20-25 hours for anyone. I just finished the game and got all badges in about 6 hours (my first time through), and I'm not particularly good at this sort of game. I died several times.
The only time THELs are semi-worthwhile is in the missions where all the enemies attack a single non-moving target. Even then pulse lasers would probably do the job better
I don't like how the enemies come from all sides but you can only fire your primary weapon up. Also the power ups look similar to some of the projectiles
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