SpaceX turned in a dominant debut. But traders are torn about the future.

Spencer Platt/Getty ImagesSpaceX climbed 19% in its stock-trading debut.Demand was strong, particularly from retail investors.After talking to a handful of institutional and retail traders, BI found a divided investor base.As I was watching SpaceX's IPO debut, I couldn't help but get some flashbacks to a young LeBron James.When LeBron entered the NBA at age 18, he was already anointed as the next big thing. This was the player who was going to challenge Michael Jordan as the basketball GOAT. And