Bonzi was not the player he used to be last year...I have a hard time believing that has changed. Perhaps if the C's trade away Scal and Tony, then they might need to look at guys like Wells...otherwise, they should hold out for someone better, or stick with what they have.
And if they are really desperate for another wing, I would take a look at Bryon Russell (on a 10 day contract) before Wells, since Russell was always a much better defender and shooter than Wells.