I have a similar array of lenses. I also had a 100mm F2.8 lens. I found it hard to handhold at close distances (Nor really Macro's) and seldom got more than 1 of 5 sharp images, so I sold it. For the most part, I got the best results with my 24-105mm IS lens, but the 135mmL was also good. I have but hate to use extension tubes, since too much setup is required, including a tripod in most cases. A 1.4 or 2X extender works better, but is still a bit klutzy.


I was pretty pessisimistic about the new 100mmL, even after reading about how many people liked it. I had recently sold my 40D and bought a used 1D MK III, so that left me with a 17-55mm lens that I reluctantly sold. I used the proceeds to buy a 100mmL, and suddenly found that closeups of flowers were easy to take handheld, even at 1/10 sec shutter speeds. This astounded me, after my previous experience.


So now, the 100mm L will be with me all the time, and is getting use as a all around telephoto on my 5d MK II as well as the 1D MK III.