I had a match where I was getting loads of headshots on TDM Sandbar, even on moving targets, but it apparently wasn't enough for some whiner who wouldn't stop following me and meleeing me like a dumbass.
Next match he ended up on the other match, destroyed him, he sent me a message saying I shouldn't hog the sniper rifle, I say I made plenty kills, too bad for you guy, get there earlier next time, he sends me a message the day after AGAIN asking if I'm mad, even though I already forgot about him. I summed up the fact that he's sending me messages for two days about a weapon pickup in a videogame and asking ME about being mad, and he never responded again.
And yeah, I also miss the starting round chatter in Gears 3 on dedicated servers, Rod addressed it a few months ago, but I can't remember if it was something that can/will be fixed.
It's taken forever, but I feel like I'm finally pretty decent with the Gnasher. I was terrible with the gun in Gears 2; when TU6 dropped, I was pretty much done. I still favor the Hammerburst a lot, and probably use it more than 98% of other players, but at least using the Gnasher isn't a liability anymore.
And King of the Hill/Annex is still my favorite game type by far. It can be a clusterfuck at times, but it's so fun.
Practice makes perfect, and when in upclose battles, practice strafing and not relying on the L-trigger for shots -hipfire is the best, and try to keep the enemy lined up with the tip of the Gnasher.