Ever since I started slinging my right arm and shoulder have been stronger than ever. I'm also more agile in that arm. I need to start working my left arm more now because my parents can actually tell the difference in size between my arms. Slight but still there.

I've also been building alot more. So that helps my arm and my hand strength. I play mercy better than ever!! :)
Start doing more sit-ups and pull-ups and I'll be the champ!

Anyone else experiance this and other positive things?

P.S. Sorry if this sounds real vain, but hey, it's pretty cool  8)

i notice when i just throw something. it's usually right on target. i used to be pathetic at throwing, but in the summer i threw a pebble at a bottle floating in a pond and sank it, first shot.  
sv

I have noticed some bulking-up of my slinging arm...nothing too visible...but a difference nonetheless.

If you see an army of bulky-armed, lopsided soldiers you better look out!! ;)

I've noticed that when I do bench press and shoulder press my rotator cuff "clicks".

Also, it helps with arm wrestling, at least the bursts of energy part of it

Iv'e noticed as well that my right arm is a tiny weiny bit bigger and also the accuracy of my right arm has improved a lot.  In every paper ball fight i am the Champ ;D

I have noticed much of a difference with  my left arm. I'm left handed, at least with writing and slashing weapons to some degree, but I am ambidextreous with most anything else, like fighting. I can punch pretty much both hands with equal facility, thats always an advantage. People can tell I'm flexing my arm when I'm wearing a jacket  ;)

One day while helping to move furniture at the house, my mom looked over at me, and saw my right bicep, and said "Jesus Christ, boy, what happened to your arm?" I thought maybe I cut it or something so I checked it over, and didn't see anything. She said ,"With muscles like that, maybe you ought to be lifting the table by yourself." I smiled and told her, "It's the slinging." She laughed at that one. As well, I've found that my hand-eye coordination has improved, if slightly. Still can't hit anything worth a d*** with the sling, though. Oh well, practice makes perfect, eh?

Lol!  :)

Man, I wish i was you!
I've only started slinging, so my arms are still their normal size  :'( ;D  
Oh well, I live in hope ;D

I haven't noticed a deference in arm size from slinging, but i have a phiysical active job and i lift weight too.