Originally posted by Qman Very true. I haven't had the dreaded X on the 18-55. Either I have a good filter, or 18mm isn't wide enough. But for my 14mm I use a single density filter to avoid the X.
Probably half my shooting is in the 10-16mm range, so I have steered away from them. They are really tempting when you are buying 77mm and 82mm filters as that amount of glass gets pricey real quick for multiple densities. I typically make due with a dark polarizer and high f-stop...not ideal, but I am cheap.