JET was never going to make it - his talent was absurd, but he was just not professional and was never going to change.
I'm surprised to hear about Randall making it. Any continuation to the story? he was mentioned as one with a future early on, but looked like the worst outcome - he was embarrassing in his latter stage here.
Think at the time I thought Jack was making it, and was undecided about Gibbs (Ricky was already saying he'll be good, I wasn't sure). Didn't think much of the others. Eastmond... actually got a chance (how pathetic was that?)