Not comparable. Korpikoski may not have a better ceiling, but right now he's a better player and has been pretty consistently for Phoenix the past two/three years.
He had 6 goals and 5 assists in 36 games last year. He's good defensively like Backlund. If anything, I'd say Backlund is a slightly better player. He had 8 goals and 8 assists in fewer games to go along with the top advanced stats on the club other than arguably Stempniak.