I've treated my 10D with a Canon 100mm macro lens - really a fine lens. I've uploaded a few results from my first experiments with it to hugoesk.de. I'm already quite satisfied with them - especially considering that they were all taken handheld. The 100mm on the 10D has a field of view similar to a 160mm lens and is therefore a nice medium telephoto focal length for me - comparable to the 180/2.8 on my Contax. Thus, it is very flexible to use and, in my opinion, worth the money. However, my previous 50mm macro won't become unemployed, even though it only goes up to 1:2: it is simply much smaller and therefore great as an all-round lens.