I have the Canon Rebel XTi using a 75-300 USM-IS lens (58mm) and would like to extend it. I was originally looking for the tele converter between the camera body and lens. Now I see there is a tele "extender" that goes on the end of the lens. (I know, where have I been?) I'd like to get opinions of anyone that uses one or the other, and which one works better for quality shots. I found some "off-brand" or Vivitar for similar prices, but the extender has a larger size thread for the filter (62mm), which means more filters to buy. So Extender vs. Converter - Which One Wins? Thanks.