I haven't shot mine a lot, but enough to get comfortable with it. It fits me pretty well.
Like most, I've had issues with releasing the mag by conventional means. My solution was that when the bolt is locked open after the last shot, remove trigger finger from guard, and while curling the whole hand slightly, slide it around underneath the trigger guard towards the mag release and use the middle finger to depress the latch. The mag will drop free leaving your off hand to insert the new mag and operate the bolt release.
I have no real issues with the factory sights except for wanting to enlarge the peep apertures for quicker target acquisition. I would probably turn down the front sight diameter a bit also, if i was going to do a lot of shooting past 100m. Otherwise, it's not really necessary. I prefer peep sights to red dot sights for my own use. I do not find them to be a hindrance at all.
Mine shoots IVI ball ammo into 2.5" @100m so it's plenty accurate. The best one could hope for performance wise, (and you can accomplish this with careful handloading with 115 and 124gr bullets) is to duplicate velocity and energy figures at 100m what you would normally get at the muzzle with a pistol.