Has any one used the Canon 320 EX Speedlite? What were your thoughts? How was it for photography? Studio? How about Video? Was the LED Video light useful or worth it? How bright is it? Do you think it is best suited for the 5 D MKII, 7d, 60D, or Rebel Series? Any other thoughts? Thinking of getting one for my 7D. I do both Stills and HD Video. I have a T3i as well. Thank you for your input.