I have two mini 14s, one ranch and one standard. Ranch model throws brass over 20 feet, brass is also spinning rapidly and goes in all directions when it hits the ground. Brass recovery rate for my ranch model is about 50%. Standard model ejects the brass within 10 feet. This is with identical loads.
Accuracy is OK, 4-5" 100 yard off hand 5 shot groups with iron sights, not much better with a scope. Reliability is very good, much less sensitive to cleanliness than my remington auto (7400), I don't own an AR so I can't really compare.
Because of the rifles lack of accuracy (compared to bolt), the ranch model's fragile rear sight and the brass ejection, I would recommend the standard model if your eyes are good.
I have heard complaints about the aftermarket mags. I don't know the mfg of my mags, I traded into a bunch of 20 and 30 rounders several years ago, they all function fine once you learn the tilt/insert/rock drill.