PS: does it do 50% more damage to synths or just the pure robot sentry type enemys?
I personally didn't care for it (too enemy type specific for me). I found myself much happier with the furious power fist that you get for free when you kill swan. little tip if you decide to go after it, if you are too low a level to face him one on one, there is a bus sitting in one of the side streets, just lure him there and shoot him with whatever you've got from the inside of the bus, I got that weapon at level 8 doing that.