The thing is only effective in an actual confrontation, which is exactly how you'd think it shouldn't be used. It would be perfect as a trap, if it weren't for the fact that it's a bright red dot that makes a bleeping noise. Jesus, 343...was the noise really necessary? At least smart players can make up for the red light by placing it behind stuff, but you still had to go and ruin it with the noise.
It's just so stupid to use in a conventional sense, because the projectile is slow and the delay between it landing and then detonating is huge, and it's not a guaranteed kill.
Had like, 4 kills left to earn another commendation with it, and I only dented the shields of like, 3 guys. With my last shot, I had a guy run RIGHT ON TOP OF IT. Detonated it, got nothing. ****in stupid weapon.