I buy UV filters for each of my lenses, but I buy the cheapest ones. My precious 28-70/2.8 sports a $25 Tiffen UV on it. I buy UVs for protection and because I hate cleaning multicoated lenses. I alway end up leaving streaks on them. I'd much rather take off a cheap UV filter, and wash it with soap and hot water than mess with the front element of my lenses. Now, about cheap filters... I don't think they effect image quality at all. They're too far inside the focal length of the lenses to be "seen", just like small dust particles inside a lens (which they ALL have), or a slight scratch on the front element of a lens has negligible impact on image quality. To test out my theory, I've taken comparitive pictures on-tripod, and can't see a nickle's worth of difference between using no filter and using a cheap UV. I see lots of you folks buying >$100 UV filters. What exactly do you think the extra $75 is buying you?