Ok here is my dilemma folks. I am a working photog in Las Vegas. I only make my living by photography. I am a bit of a jack of all trades, with no set Niche. I do very well out here. However its time where i realize i need a longer lens.... Currently my kit includes: 30d and 40d 20 1.8 30 1.4 10-22 70-200 2.8 + 1.4x when needed 18-50 2.8 I use all these lenses for different reasons: Primes and std zoom for events, night clubs, and concerts UWA and std zoom for Real Estate 70-200 for kids sports and "celeb" work Im looking for more reach for "celeb" shots and kids football. my budget is shy of $1000 and i need a zoom. I also need quality glass. I dont care if its an L or Sigma. Sigma has always done me right. and every L ive used or owned left me wanting for the price i paid. So what i was thinkg is getting a 100-300 f4 with use of my extender when needed. But some love teh quality of the Bigma. Anyone here used both? I hear the 100-300 f4, is almost on par with the 300 f4 L... and f4 is great for shots when i need a bit of speed (i would get the 120-300 2.8 if it wasnt out of my price range) im more or less 60% getting the 100-300.. but the extra 100mm is really in my mind when dealing with the Bigma.... I need your help.