Tines or Knife Blades For Cleanup??

[JW1]

I have been told that tine dethatchers are superior over knife blades on a power rake for spring clean up on a lawn. I am looking for a small power rake to do spring cleanups this year and not sure what attachment to get for it. Anybody have a preference? How do you pick up the dead grass after. Vacuum or bag on you power rake? Some say the bag on a power rake is a waste of money as it just clogs up anyway. Anyone with before and after pictures would be great too. Thanks, Jim.