Go to a 3 gun match. I have shot the local 3 gun match twice now. I only saw on rifle that was not an AR-15. It was mine-a Mini 14 Target Model with a Weaver 6-20x42 scope.
I beat about half the guys in my squad on the rapid fire accuracy stage. They had an advantage with weight and muzzle rise, and maneuverability. This was last November. This month, I used my new (well, used) AR-15. It was a 20" H-bar with stock hand guards and an A2 stock. After the match last weekend, I had the barrel turned down to a medium profile rather than Hbar, had it cut to 18" and a free float hand guard and comp installed. I run a Cmore sight because I already had the optic. Unfortunately the match for tomorrow was canceled due to rain, otherwise I would be competing with mine.
It was easy to modify the AR-15 to my needs. My Mini was bought, and designed to be shot only with a scope and it was made for precision shots in which the gun didn't have to be small or light weight. It is very well suited for shooting from the bench, which was my intended use when I bought it.
The Antis don't think and don't want to admit that AR-15's have a legitimate use. Not knowing is not believing.
Want to know the truth? As of two months ago, I didn't see a big need for an AR-15 either. I didn't have a problem with them, but it seemed like it was just the new fad. I shot a few and didn't mind them. When I tried 3 gun, I learned that they may have a purpose for me. Knowing that, I jumped on the band wagon when I heard of possible new bans. It pushed my schedule for buying one, as much as a year sooner than expected. I am now very glad I pulled the trigger. I still have and like my Mini, but I really do love my AR.
I really wish I cold run without the stupid bullet button and that I could use 30 round mags in 3 gun.
Sporting with guns pretty much sums up a big part of my way of life. I don't wish to hunt and I hope not to have to shoot a person. I have been addicted to competitive pistol shooting for 3 years, now rifles and shotguns too. My semi auto skeet shotgun (Benelli Super Sport) isn't well suited for 3 gun. It holds only 5 rounds and is very long. I make due with it, for 3 gun. One of those evil assault shotguns would be great for competition. The Saga is popular with some people, in competition, as are the Benellis with extended mags and short barrels.
I have fired 0 rounds towards animals or people, and maybe 60-100k rounds for fun/pleasure and skill building. I have 30k through my XD competition pistol. Sporting is my primary use, but the right to defend myself against attackers, including a tyrannical government, is my most important reason for owning fire arms. I do have other hobbies, but they will not protect me from harm, the way firearms will.