I already have a blower from ebay that served me fairly well. still has got some speck on my 550D sensor. I do not want to go canon service center for cleaning yet because there are not many specks. Im looking at Giottos. I wonder how is Giottos more superior than my blower from ebay beside that it sucks air from the valve at its bottom? maybe it blows some kind of charged air that can dislodge dust?
And is the large size one more powerful than medium? or it depends on the tip - the smaller the more powerful?