Last year for the whole damn season, Al-Farouq Aminou was fourth, ahead of James and some other guys people have actually watched play. I've had this discussion (argument) with a couple of guys here before. Real Plus Minus, just like RAPM, tells you a few things everybody already knows - like "Kawhi Leonard is a damned good defender". And then it tells you a bunch of things that are just patently false - like "Al-Farouq Aminou is a better defender than LeBron".
The problem with them is, you don't need them to tell you things that EVERYBODY already knows. And you don't need them to tell you things that are patently false. So, bottom line, you don't need them at all. Just a suggestion, but you should consider not bothering to look at them.