Repeating 8th grade is very common here (Southern California), along with the virtual home school. The kid enters freshman year and is bigger and stronger than his peers, and if he's a good ball player he looks like a stud. This gets the kid to varsity faster, and with PG now using the players grade for tournaments, it helps in those events too. I think this definitely gets the kid looks from colleges earlier, and perhaps looks that he wouldn't have gotten.
Risks? I've seen some of these "stud" freshman lose their edge as their peers catch up. The perception (and maybe reality) is that they aren't improving, that they sort of peaked and plateaued early. By Junior year people are wondering what happened to that kid and how is he going to survive at Big Name school.