I loved this gun in ME2, the damage was insane and the laser sight was incredible. I was pumped when I heard that ME3 would let you modify weapons and that the Phalanx wouldn't come with a laser sight by default. I was hoping that the laser sight would be a mod for all pistols.
Then ME3 came out and there was no laser sight and the Phalanx damage was nerfed considerably... Needless to say I was really bummed.
I actually hoped for a laser sight mod for different weapons. It's probably just too difficult to implement something like that. Or the feedback for the laser sight just wasn't good enough for them to bother with.