Honestly, as long as that little chain thing isn’t drilled into the receiver (and it looks magnetic) the rifle can be returned to OEM pretty easily.
It’s not overly tacky or anything; railed top cover, adjustable stock, relatively chill KUSA handguard. The things that upset me the most are the 5.45 mags trying to be 5.56 mags. “All you need is a 3d printed follower!” No - that’s bad and you should feel bad. There are plenty of correct 5.56 mags that work in the 106 family now.
All that said, one man’s “custom” is another’s “dragged through a Tapco catalog” so returning it to stock before selling it would be prudent.