Honestly I don't much about guns lol. I just know the Beretta 9mm I bought is a well respected, reliable, and very accurate gun. Although I get stopping power jokes all the time from .45 diehards.
I just know that gun (my friend had Ar10) with a quality muzzle brake had very little kick, and once we got the scope scoped in it reliably hits at 150 yards and real solid at 300. I have shot a rocky river(? Or was it ridge?) AR15 and enjoyed it. But it jammed quite a bit. But that was more a product of a new gun and terrible powder coated Russian ammo. You really have to fire good brass through some guns when they are new, and some guns just don't like powder coated ammo no matter how much use they have.
All I know is between the AR15s I have fired and the one AR10 I have fired, the AR10 was amazing. But in fairness my friend had a really top quality AR10 with quality accessories, while my friends just bought theirs and knew only slightly more than I do.
Before I ever considered dropping that type of money I would most definitely do some research and go fire some different types.