I had a similar experience with one of the standard UV filters. I bought it on the recommendation of a friend.When I complained to him that I thought the images were a little soft, and maybe he had steered me wrong we got together to compare. What I discovered is that I paid around $30 for my filter and he had paid almost $100. Both Promaster UV filters. The salesman tried to sell me the better filter but did a really bad job of explaining why I needed it except it was easier to clean. I took the filter back to the store to return it and get a B+W. The store manager took the time to explain the real difference between the standard filter and the better filters including both the B+W and the Promaster better filter. It seems that most of the inexpensive filters from Hoya, Tiffen, Sunpak, Promaster, or others are only coated on one side of the glass or not coated at all. The higher end filters are coated both sides with multiple layers of coating that helps eliminate the ghosting which impacts the image sharpness. Anyway, the manager convinced me to trade for the Promaster HGX and save the extra $30 since it had the same level of coating etch as the B+W MRC. They said if I was unhappy, they would swap me for the B+W. So far, no soft images and I am as happy as my friend.