I personally think it'd be better for him to go. May not be whats best for NU but best for Brandon.
Like it was said, the RB class coming out wont be as big and tough...he is hot right now, and gave a great showing.
Main reason I think he should go, there is no telling what will happen between now and the end of next season. He has to think about having Marlon Lucky and Cody Glenn behind him...his spot isnt "safe". They could work their a$$ off in spring and sit him back in 3rd or 4th string. Thats the main reason I think it'd be best for him to go...get out while you're hot and people know you.