I've been using one for a few years now and have always been pleased with the results. I tend to use the primes for studio work, especially portraiture, but love using the lens in the field because of its versatility. When stoppped down to f8, I can see little difference between its results and those of the primes - and distortion is so minimal as to be of no consequence. If you don't need the speed, it can allow you to leave the 110, 180 and 210/250 lenses at home. In the field, I tend to take either the 50 or 65, the zoom, and perhaps the 1.4x teleconverter or the 360mm. If I know I'll be shooting architecture, then I'll leave the long telephoto and take the 75 shift, no laughing matter as it's heavier than the zoom. Unless you plan to use the 100-200 for close focusing/macro at around 0.5m, you can dispense with the support bracket (and save quite a lot of money if you buy second hand as lenses without can go for as little as $180 at K*H or on ebay). Buy it new and it comes with the bracket which has also been designed to accommodate the Winder - a boon if you use certain digital backs. At the low prices right now, I'd be tempted to buy...I've got 2 and have never regretted them.